Experimental Enthalpy Increments from the Solid Phases to the Liquid

J. Chem. Eng. Data 2003, 48, 497-513

497

Experimental Enthalpy Increments from the Solid Phases to the Liquid Phase of Homologous n-Alkane Series (C18 to C38 and C41, C44, C46, C50, C54, and C60) Anne-Julie Briard, Mohammed Bouroukba, Dominique Petitjean, Nathalie Hubert, and Michel Dirand* Laboratoire de Thermodynamique des Milieux Polyphase´s EA No. 3099, Ecole Nationale Supe´rieure des Industries Chimiques, Institut National Polytechnique de Lorraine, 1, rue Grandville, BP 451, F-54001 Nancy Cedex, France

Measurements of enthalpy increments from the temperature of the ordered phases of low temperatures at 293.4 K and 298.3 K up to the liquid phase above the melting point were carried out by differential scanning calorimetry using a discontinuous mode of temperature programming on the n-alkanes from C18 to C38 and C41, C44, C46, C50, C54, and C60. The temperatures and enthalpies of the solid-solid transitions and of the fusion were also determined and compared with the values of the literature.

Introduction Because of the importance of the n-alkanes (hereafter denoted by Cn), numerous studies1-83 have been carried out to determine their thermodynamic properties and their structural behavior. Although numerous values of the temperatures and enthalpies of solid-solid and solidliquid transitions of Cn’s are available in the literature,1-85 only some authors (Messerly et al.;7 Finke et al.;10 Schaerer et al.;16,40 Barbillon et al.;19 Parks et al.;34 Andon and Martin;46 Jin and Wunderlich;57 Van Miltenburg85) have carried out measurements of the variations of thermodynamic properties (enthalpies, entropies) of light Cn’s (n < 27) with respect to the temperature from the ordered solid phases of low temperatures up to the liquid phase above the melting point: these data types are still less numerous for the heavy Cn’s (n > 26). The aim of this article is to determine the enthalpy increments of the n-alkanes from C18 to C38 and C41, C44, C46, C50, C54, and C60, as a function of the increasing temperature by differential scanning calorimetry. Structural BehaviorsLiterature Results Cn Crystalline Structures of Low Temperatures. The crystallographic structures of ordered phases at low temperatures have been studied by Craig et al.,64 who identified the crystallographic space groups, and Chevallier et al.,72 who correlated the crystalline long c-parameter with the number of carbon atoms of pure Cn chains: (i) oddnumbered C2p+1’s have an orthorhombic structure, described by Smith66 for the C23 with the crystallographic space group Pbcm;64 (ii) even-numbered C2p’s with 14 e 2p e 26 have the triclinic structure described by Mu¨ller67 and Nyburg et al.65,68 for the C18 whose space group is P1 h; C2p’s with 28 e 2p e 36 have a monoclinic structure, determined by Shearer and Vand69 for the C36 with the P21/a crystallographic space group; C2p’s with 2p ) 38, 40, and 44 have a Pbca orthorhombic structure, described by Boistelle et al.;70 and C2p’s with 2p > 44 have a Pca21 * Corresponding author. Telephone: 33.(0)3.83.17.50.07. 33.(0)3.83.17.50.76. E-mail: [email protected].

Fax:

Figure 1. DSC curve of the n-alkane C29 with increasing temperature: observation of δ and γ order-order transitions below the order-disorder transition and the melting.

orthorhombic structure, determined by Shearer and Vand69 and Teare.71 Cn Structural Behavior versus Temperature. Mu¨ller73,74 was the first to observe polymorphism by X-ray diffraction in Cn, over a range of temperature, particularly in disordered phases below the melting point. From the literature data,50-80 Chevallier et al.83 and Dirand et al.84 classified these polymorphic transitions according to the following behavior (Scheme 1) with respect to the increasing temperature: For the pure Cn’s, it is possible to distinguish two categories of polymorphic phases: (i) the ordered phases of low temperatures, observed below the order-disorder transition temperature, To-d, and (ii) the disordered phases of high temperatures that can present molecular movements of the Rotator type: orthorhombic β-RI (Fmmm), rhombohedral R-RII (R3 h m), triclinic RIII, and monoclinic RIV disordered structures. The order-disorder solid-solid transition (hereafter named the o-d transition) is characterized by the higher thermal effect observed at the solid state below the melting point (Figure 1). Other polymorphic transitions, with which

10.1021/je0201368 CCC: $25.00 © 2003 American Chemical Society Published on Web 04/08/2003

498

Journal of Chemical and Engineering Data, Vol. 48, No. 3, 2003

Scheme 1a

a f corresponds to first-order transitions. w corresponds to second- or higher-order transitions. The o-d transition disappears from C45.53,54,77

lower thermal effects are associated, appear in each category:83,84 (i) order-order transitions below the o-d transition [δ-transition,75 which corresponds to the phase change β0 (orthorhombic Pbcm) f β′0 (orthorhombic Pbnm); γ-transition,83,75 corresponding to β0 (orthorhombic Pbcm) f B (monoclinic Aa); and β-transition,55,56,75 corresponding to B (monoclinic Aa) f C (monoclinic A2)]; (ii) disorder T disorder transitions between the o-d transition temperature and the melting point (Scheme 1). The temperatures and enthalpies of solid-solid and solid-liquid transitions of Cn’s were reported as a function of the carbon atom number of the Cn chain from the methane up to the Cn with n equal to 390 by Dirand et al.84 Experimental Section Principle of Measurement and Operating Conditions. The measurement of the enthalpy increments was deduced from differential thermal analyses, performed with

a differential scanning calorimeter of the Tian-Calvet type,86 using a discontinuous mode of temperature programming. The calorimeter principle has been described before.86-89 The calorimeter temperature is programmed as shown in Figure 2, it increases linearly between T1 and T2 during time ti and is then constant at T2 during time tl. Thus, the calorimeter temperature increases step by step from room temperature up to the maximum temperature of the experiment. The device measures the difference in heat flows that are exchanged between the two cells and the calorimeter block; it is evaluated by measurement of the electromotive force, ∆E, developed in two thermopiles surrounding the two calorimeter cells and connected together in opposition. ∆E, measured in the course of a temperature jump from T1 to T2 during time ti + tl, is related to the difference in heat, Q, exchanged between the two cells and the calorimeter block, by means of the sensitivity coefficient, S(T),

Journal of Chemical and Engineering Data, Vol. 48, No. 3, 2003 499 Table 1. Purity of the n-Alkanes Used in This Study

Figure 2. Calorimetric signal and temperature jump.

name

symbol

purity/%

octadecane nonadecane eı¨cosane heneicosane docosane tricosane tetracosane pentacosane hexacosane heptacosane octacosane nonacosane triacontane hentriacontane dotriacontane tritriacontane tetratriacontane pentatriacontane hexatriacontane heptatriacontane octatriacontane hentetracontane tetratetracontane hexatetracontane pentacontane tetrapentacontane hexacontane

C18H38 C19H40 C20H42 C21H44 C22H46 C23H48 C24H50 C25H52 C26H54 C27H56 C28H58 C29H60 C30H62 C31H64 C32H66 C33H68 C34H70 C35H72 C36H74 C37H76 C38H78 C41H84 C44H90 C46H94 C50H102 C54H110 C60H122

≈99 ≈98 g97 g98 g98 g98 g99 g98 g99 g98 g98 g99.5 g98 g99.5 ≈98 >97 g97 g99.5 ≈98 g99 >98 g99 ≈99 g98 g97 ≈99 >98

Table 2. Comparison of the Experimental Enthalpy T Increments (H293.4 ) versus Temperature of the n-Alkane T (lit.)7) C18H38 with the Literature Data7 (H293.4

Figure 3. Enthalpy curve for the even n-alkane C26: ∆Htot ) fus fus ∆HTTo-d ) ∆Ho-d + ∫TTo-d Cp dT + ∆fusH.

Ta

Τ H293.4

Τ H293.4 (lit.)7

K

kJ‚mol-1

kJ‚mol-1

% diff

293.4 (s) 319.9 (l) 330.2 (l) 340.4 (l) 350.6 (l) 360.8 (l)

0 76.7 82.2 88.0 93.7 99.3

0 74.9 81.0 87.1 93.3 99.4

2.3 1.4 1.0 0.5 0.1

a In parentheses is the state of the n-alkane at that temperature: l, liquid; s, solid.

Table 3. Comparison of the Experimental Enthalpy T ) versus Temperature of the n-Alkane Increments (H293.4 T C26H54 with the Literature Data46 (H293.4 (lit.)46)

Figure 4. Enthalpy curve for the odd n-alkane C29: ∆Htot ) fus fus ∆HTTo-d ) ∆Ho-d + ∫TTo-d Cp dT + ∆fusH.

determined by calibration.

Q)

1 S(T)

∫

t2

t1

∆E dt

The sensitivity coefficient, S(T), was obtained with respect to temperature variations by calibration with the

T

Τ H293.4

Τ H293.4 (lit.)46

K

kJ‚mol-1

kJ‚mol-1

% diff

293.4 (s) 300.5(s) 309.7(s) 319.9(s) 330.1 (l) 340.4 (l) 350.6 (l) 360.8 (l)

0 4.6 10.7 17.7 124.3 132.7 140.5 147.7

0 4.6 10.7 17.9 121.9 130.7 139.5 148.4

0.6 0.3 1.1 1.9 1.5 0.7 0.5

help of the thermodynamic data on alumina, reported in the N.B.S. Table,90 and on the two metals gallium and indium. The change in enthalpy of the sample was obtained as the difference in heat transfer in two experiments. In the blank experiment both cells were empty. The observed heat is the asymmetric term, Qa. In the other experiment a sample is placed in one of the cells. It gives the total heat transferred, Q0. The difference is the heat transferred to the sample, Qs.

Qs ) Q 0 - Q a

500


T Table 4. Thermodynamic Data of C18: Temperature (T ( 0.5)/K; Enthalpy Values Referred to 293.4 K (H293.4 /kJ‚mol-1, % diff: 1.5%); Phase Name

T K 293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.7 307.7 308.7 309.7 310.8 311.8 312.8

Τ H293.4

kJ‚mol-1 phase 0.0 0.6 1.3 2.1 2.9 4.1 6.4 19.6 66.5 67.1 67.6 68.2 68.8 69.4 69.9 70.5 71.1 71.7 72.2 72.8

Τ H293.4

T γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) L L L L L L L L L L L L L

kJ‚mol-1 phase

K 313.8 314.8 315.9 316.9 317.9 318.9 320.0 321.0 322.0 323.0 324.0 325.1 326.1 327.1 328.1 329.1 330.2 331.2 332.2 333.2

Τ H293.4

T

73.4 74.0 74.5 75.1 75.6 76.2 76.7 77.2 77.7 78.3 78.8 79.4 79.9 80.5 81.0 81.6 82.2 82.8 83.4 83.9

kJ‚mol-1 phase

K

L L L L L L L L L L L L L L L L L L L L

334.3 335.3 336.3 337.3 338.4 339.4 340.4 341.4 342.4 343.5 344.5 345.5 346.5 347.6 348.6 349.6 350.6 351.7 352.7

84.5 85.1 85.7 86.3 86.9 87.4 88.0 88.6 89.2 89.8 90.3 90.9 91.5 92.0 92.6 93.2 93.7 94.3 94.8

Τ H293.4

T L L L L L L L L L L L L L L L L L L L

T

kJ‚mol-1 phase

K 353.7 354.7 355.7 356.8 357.8 358.8 359.8 360.9 361.9 362.9 363.9 364.9 365.9 367.0 368.0 369.0 370.0 371.1 372.1

95.4 95.9 96.5 97.0 97.6 98.1 98.7 99.3 99.8 100.4 100.9 101.4 102.0 102.5 103.1 103.6 104.2 104.7 105.3

L L L L L L L L L L L L L L L L L L L

K 373.1 374.1 375.1 376.2 377.2 378.2 379.2 380.3 381.3 382.3 383.3 384.4 385.4 386.4 387.5 388.5 389.5 390.6 391.6

Τ H293.4

kJ‚mol-1 phase 105.9 106.4 107.0 107.5 108.1 108.6 109.2 109.8 110.4 111.0 111.6 112.2 112.9 113.5 114.1 114.7 115.4 116.0 116.6



T

Τ H293.4

Τ H293.4

K

kJ‚mol-1

phase

K

293.4 294.4 295.4 296.4 297.4 298.4 299.5 300.5 301.5 302.5 303.5 304.6 305.6 306.6 307.6 308.7 309.7 310.7 311.7 312.8

0.0 0.8 10.6 13.6 14.7 15.8 17.1 18.5 20.1 22.1 25.4 43.6 67.3 67.9 68.6 69.2 69.9 70.5 71.2 71.8

β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) L L L L L L L L L

313.8 314.8 315.8 316.8 317.8 318.9 319.9 320.9 321.9 323.0 324.0 325.0 326.0 327.0 328.1 329.1 330.1 331.1 332.2 333.2

T

Τ H293.4

T

kJ‚mol-1 phase 72.5 73.2 73.8 74.5 75.1 75.8 76.4 77.1 77.8 78.4 79.1 79.7 80.4 81.1 81.7 82.4 83.1 83.8 84.4 85.1

kJ‚mol-1 phase

K


334.2 335.2 336.3 337.3 338.3 339.3 340.3 341.4 342.4 343.4 344.4 345.5 346.5 347.5 348.5 349.5 350.5 351.6 352.6 353.6

Τ H293.4

T

85.8 86.4 87.1 87.8 88.5 89.2 89.9 90.6 91.3 92.0 92.7 93.4 94.1 94.8 95.6 96.3 97.0 97.6 98.3 99.0


T

kJ‚mol-1 phase

K 354.6 355.6 356.6 357.7 358.7 359.7 360.7 361.7 362.8 363.8 364.8 365.8 366.9 367.9 368.9 369.9 370.9 372.0 373.0

99.7 100.5 101.2 101.9 102.7 103.4 104.1 104.8 105.5 106.3 107.0 107.7 108.4 109.2 109.9 110.7 111.4 112.1 112.9


K 374.0 375.0 376.1 377.1 378.1 379.2 380.2 381.2 382.2 383.2 384.3 385.3 386.3 387.3 388.4 389.4 390.4 391.5 392.5

Τ H293.4

kJ‚mol-1 phase 113.6 114.3 115.1 115.8 116.6 117.3 118.1 118.8 119.6 120.4 121.1 121.9 122.6 123.4 124.2 124.9 125.7 126.5 127.3



T K 293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8

Τ H293.4

T

kJ‚mol-1 phase 0.0 0.6 1.1 1.7 2.3 2.8 3.4 4.0 4.7 5.3 5.9 6.5 7.1 7.8 8.6 9.7 82.7 83.4 84.1 84.8

γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) L L L L L

K 313.8 314.8 315.8 316.9 317.9 318.9 319.9 321.0 322.0 323.0 324.0 325.0 326.1 327.1 328.1 329.1 330.1 331.2 332.2 333.2

Τ H293.4

T

kJ‚mol-1 phase 85.5 86.2 86.9 87.6 88.3 89.0 89.8 90.5 91.2 91.9 92.6 93.3 94.0 94.7 95.4 96.2 96.9 97.6 98.3 99.0


K 334.2 335.2 336.3 337.3 338.3 339.3 340.4 341.4 342.4 343.4 344.5 345.5 346.5 347.5 348.5 349.6 350.6 351.6 352.6 353.7

Τ H293.4

T

kJ‚mol-1 phase 99.8 100.5 101.2 102.0 102.7 103.4 104.2 104.9 105.6 106.4 107.1 107.9 108.6 109.4 110.1 110.9 111.7 112.4 113.2 114.0


K 354.7 355.7 356.7 357.7 358.8 359.8 360.8 361.8 362.9 363.9 364.9 365.9 366.9 368.0 369.0 370.0 371.0 372.1 373.1

Τ H293.4

T

kJ‚mol-1 phase 114.8 115.6 116.3 117.1 117.9 118.7 119.4 120.2 121.0 121.7 122.5 123.3 124.1 124.9 125.7 126.5 127.3 128.1 128.9


K 374.1 375.1 376.1 377.2 378.2 379.2 380.2 381.2 382.3 383.3 384.3 385.4 386.4 387.4 388.4 389.4 390.5 391.5 392.5

Τ H293.4

kJ‚mol-1 phase 129.7 130.5 131.3 132.1 132.9 133.7 134.5 135.3 136.1 136.9 137.8 138.6 139.4 140.2 141.0 141.9 142.7 143.6 144.4


Journal of Chemical and Engineering Data, Vol. 48, No. 3, 2003 501 T Table 7. Thermodynamic Data of C21: Temperature (T ( 0.5)/K; Enthalpy Values Referred to 298.3 K (H298.3 /kJ‚mol-1, % diff: 1.5%); Phase Name

T

Τ H298.3

K

kJ‚mol-1

phase

K

298.3 299.4 300.4 301.4 302.4 303.4 304.5 305.5 306.5 307.5 308.6 309.6 310.6 311.6 312.6 313.7 314.7 315.7 316.7 317.8 318.8 319.8 320.8 321.9 322.9 323.9 324.9 325.9

0.0 0.6 1.2 1.8 2.5 3.1 3.9 20.5 21.9 23.5 25.2 27.0 28.9 30.6 32.3 79.9 80.6 81.2 81.9 82.5 83.2 83.9 84.5 85.2 85.9 86.5 87.2 87.9

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) L L L L L L L L L L L L L L

327.0 328.0 329.0 330.0 331.0 332.1 333.1 334.1 335.1 336.2 337.2 338.2 339.2 340.2 341.3 342.3 343.3 344.3 345.4 346.4 347.4 348.4 349.4 350.5 351.5 352.5 353.5

T

Τ H2938.3

T

kJ‚mol-1 phase 88.6 89.2 89.9 90.5 91.2 91.8 92.5 93.2 93.8 94.5 95.2 95.9 96.5 97.2 97.9 98.6 99.3 99.9 100.6 101.2 101.9 102.6 103.2 103.9 104.6 105.2 105.9

L L L L L L L L L L L L L L L L L L L L L L L L L L L

K 354.6 355.6 356.6 357.6 358.6 359.7 360.7 361.7 362.7 363.8 364.8 365.8 366.8 367.8 368.9 369.9 370.9 371.9 373.0 374.0 375.0 376.0 377.1 378.1 379.1 380.1 381.2

Τ H298.3

T

kJ‚mol-1 phase 106.6 107.3 108.0 108.6 109.3 110.0 110.6 111.3 112.0 112.7 113.3 114.0 114.7 115.4 116.1 116.8 117.5 118.2 118.9 119.5 120.2 120.9 121.6 122.4 123.1 123.8 124.5


K 382.2 383.2 384.2 385.3 386.3 387.3 388.3 389.4 390.4 391.4 392.4 393.5 394.5 395.5 396.5 397.6 398.6 399.6 400.7 401.7 402.7 403.7 404.8 405.8 406.8 407.9 408.9

Τ H2938.3

kJ‚mol-1 phase 125.2 125.9 126.6 127.3 128.0 128.7 129.4 130.1 130.9 131.6 132.3 133.0 133.7 134.4 135.1 135.8 136.5 137.2 137.9 138.6 139.3 140.0 140.8 141.5 142.2 142.9 143.6

Τ H2938.3

T K


kJ‚mol-1 phase

409.9 411.0 412.0 413.0 414.0 415.1 416.1 417.1 418.2 419.2 420.2 421.2 422.3 423.3 424.3 425.4 426.4 427.4 428.5 429.5 430.5 431.6 432.6 433.6 434.7 435.7 436.7

144.4 145.1 145.8 146.6 147.3 148.1 148.8 149.6 150.3 151.1 151.8 152.5 153.3 154.1 154.8 155.6 156.3 157.1 157.9 158.7 159.5 160.2 161.0 161.8 162.7 163.5 164.3



T

Τ H298.3

K

kJ‚mol-1

phase

K

298.3 299.4 300.4 301.4 302.4 303.4 304.5 305.5 306.5 307.5 308.6 309.6 310.6 311.6 312.7 313.7 314.7 315.7 316.7 317.7 318.8 319.8 320.8 321.8 322.9 323.9 324.9 325.9

0.0 0.7 1.3 2.0 2.6 3.3 3.9 4.6 5.2 5.9 6.6 7.3 7.9 8.6 9.3 10.1 10.8 11.7 43.4 92.5 93.3 94.1 94.8 95.6 96.4 97.2 98.0 98.7

h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 R-RII (R3 h m) R-RII (R3 h m) R-RII (R3 h m) R-RII (R3 h m) L L L L L L L L L L L

326.9 328.0 329.0 330.0 331.0 332.1 333.1 334.1 335.1 336.1 337.2 338.2 339.2 340.2 341.3 342.3 343.3 344.3 345.3 346.4 347.4 348.4 349.4 350.5 351.5 352.5 353.5

T

Τ H2938.3

T

kJ‚mol-1 phase 99.5 100.3 101.1 101.9 102.7 103.5 104.2 105.0 105.8 106.6 107.3 108.1 108.9 109.7 110.5 111.3 112.1 112.9 113.6 114.4 115.2 116.0 116.8 117.6 118.4 119.1 119.9


K 354.5 355.6 356.6 357.6 358.6 359.7 360.7 361.7 362.7 363.8 364.8 365.8 366.8 367.8 368.9 369.9 370.9 371.9 373.0 374.0 375.0 376.0 377.1 378.1 379.1 380.1 381.1

For each temperature jump, j, the molar enthalpy increment of the sample is as follows:

∆HTT12 ) H°(T2) - H°(T1) )

M (Q ) m sj

where M and m are the molar mass and the mass of the sample, respectively. The molar enthalpy increment above

Τ H298.3

T

kJ‚mol-1 phase 120.7 121.5 122.3 123.1 123.9 124.6 125.4 126.2 127.0 127.8 128.6 129.4 130.2 131.0 131.8 132.6 133.4 134.2 134.9 135.7 136.5 137.3 138.1 138.9 139.7 140.5 141.4


K 382.2 383.2 384.2 385.3 386.3 387.3 388.3 389.4 390.4 391.4 392.4 393.5 394.5 395.5 396.5 397.6 398.6 399.6 400.7 401.7 402.7 403.7 404.8 405.8 406.8 407.8 408.9

Τ H2938.3

kJ‚mol-1 phase 142.1 142.9 143.7 144.6 145.4 146.2 147.1 147.9 148.7 149.5 150.4 151.2 152.0 152.9 153.7 154.6 155.5 156.3 157.1 157.9 158.7 159.5 160.3 161.1 161.8 162.6 163.4

Τ H2938.3

T K


kJ‚mol-1 phase

409.9 410.9 412.0 413.0 414.0 415.0 416.1 417.1 418.1 419.2 420.2 421.2 422.2 423.3 424.3 425.3 426.4 427.4 428.4 429.5 430.5 431.5 432.6 433.6 434.6 435.7 436.7

164.2 165.1 165.9 166.8 167.7 168.5 169.4 170.2 171.1 172.0 172.8 173.7 174.5 175.4 176.2 177.1 178.0 178.9 179.8 180.7 181.5 182.4 183.3 184.2 185.1 186.0 186.9


T0 of the sample heating at temperature T, with T0 equal to 293.4 K or 298.3 K, is as follows:

HTT0 ) H(T) - H(T0) )

M

∑m(Q )

s j

j

where H(T) and H(T0) are the enthalpies at T and T0, respectively.

502



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8

0.0 0.6 1.2 1.9 2.5 3.2 3.9 4.5 5.2 5.9 6.6 7.3 8.0 8.7 9.5 10.2 10.9 11.7 12.5 13.8

T

Τ H293.4

Τ H293.4

phase

K

kJ‚mol-1

phase

K

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β′0 (Pbnm) β′0 (Pbnm) β-RI (Fmmm)

313.8 314.8 315.8 316.8 317.9 318.9 319.9 320.9 321.9 323.0 324.0 325.0 326.0 327.0 328.0 329.1 330.1 331.1 332.1 333.2

36.4 38.9 41.1 43.0 44.6 45.8 47.4 100.3 101.1 101.9 102.7 103.5 104.2 105.0 105.8 106.6 107.4 108.2 108.9 109.7

β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) R-RII (R3h m) R-RII (R3h m) R-RII (R3h m) L L L L L L L L L L L L L L

334.2 335.2 336.2 337.3 338.3 339.3 340.3 341.4 342.4 343.4 344.4 345.4 346.5 347.5 348.5 349.5 350.5 351.6 352.6 353.6

T

Τ H293.4

T

kJ‚mol-1 phase 110.5 111.3 112.1 113.0 113.8 114.6 115.4 116.2 117.0 117.8 118.6 119.4 120.3 121.1 121.9 122.7 123.6 124.4 125.2 126.1


T

kJ‚mol-1 phase

K 354.6 355.7 356.7 357.7 358.7 359.8 360.8 361.8 362.8 363.8 364.9 365.9 366.9 367.9 368.9 370.0 371.0 372.0 373.0

126.9 127.8 128.7 129.6 130.4 131.3 132.2 133.1 134.0 134.9 135.8 136.7 137.5 138.4 139.3 140.2 141.1 142.0 143.0


K 374.1 375.1 376.1 377.1 378.2 379.2 380.2 381.2 382.3 383.3 384.3 385.3 386.4 387.4 388.4 389.4 390.5 391.5 392.5

Τ H293.4

kJ‚mol-1 phase 143.9 144.7 145.6 146.5 147.4 148.3 149.2 150.1 151.0 151.9 152.8 153.7 154.6 155.4 156.4 157.3 158.2 159.1 160.0



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.6 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8

0.0 0.6 1.3 1.9 2.5 3.2 3.8 4.5 5.1 5.8 6.5 7.1 7.8 8.5 9.2 9.9 10.6 11.3 12.0 12.7

T

Τ H293.4

Τ H293.4

phase

K

kJ‚mol-1

phase

K

γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) h) γ0 (P1 γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) h) γ0 (P1 γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) h) γ0 (P1 γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h)

313.8 314.8 315.9 316.9 317.9 318.9 319.9 321.0 322.0 323.0 324.0 325.0 326.0 327.1 328.1 329.1 330.1 331.2 332.2 333.2

13.5 14.2 14.9 15.7 16.4 17.2 18.1 47.8 51.1 53.0 110.3 111.1 111.9 112.7 113.6 114.4 115.2 116.0 116.9 117.7

γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) R-RII (R3h m) R-RII (R3h m) R-RII (R3h m) L L L L L L L L L L L

334.2 335.3 336.3 337.3 338.3 339.4 340.4 341.4 342.4 343.4 344.5 345.5 346.5 347.5 348.5 349.6 350.6 351.6 352.6

T

T

kJ‚mol-1 phase 118.5 119.4 120.2 121.0 121.9 122.7 123.5 124.4 125.2 126.0 126.9 127.7 128.5 129.3 130.1 130.9 131.7 132.6 133.4


K 353.6 354.7 355.7 356.7 357.7 358.7 359.8 360.8 361.8 362.8 363.9 364.9 365.9 366.9 367.9 369.0 370.0 371.0 372.0

Τ H293.4

T

kJ‚mol-1 phase 134.2 135.0 135.8 136.6 137.5 138.3 139.1 140.0 140.8 141.7 142.5 143.4 144.2 145.1 146.0 146.8 147.7 148.6 149.5


K 373.0 374.1 375.1 376.1 377.1 378.2 379.2 380.2 381.2 382.3 383.3 384.3 385.4 386.4 387.4 388.5 389.5 390.5 391.5

Τ H293.4

kJ‚mol-1 phase 150.4 151.3 152.2 153.1 154.0 154.9 155.8 156.7 157.6 158.6 159.5 160.4 161.3 162.2 163.1 164.1 165.0 166.0 167.0



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.4 299.5 300.5 301.5 302.5 303.5 304.6 305.6 306.6 307.6 308.7 309.7 310.7 311.7 312.8

0.0 0.7 1.3 1.9 2.6 3.3 4.0 4.7 5.4 6.1 6.9 7.6 8.4 9.1 9.9 10.6 11.4 12.2 13.2 14.2

T

Τ H293.4

phase

K

kJ‚mol-1

phase

K

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm)

313.8 314.8 315.8 316.8 317.9 318.9 319.9 320.9 321.9 323.0 324.0 325.0 326.0 327.0 328.1 329.1 330.1 331.1 332.2 333.2

15.1 16.0 17.0 18.0 19.1 20.6 37.9 48.1 50.4 52.9 56.5 63.2 89.0 113.3 114.2 115.1 116.0 116.9 117.8 118.7

β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) B (Aa) B (Aa) β-RI (Fmmm) β-RI (Fmmm) β-RI (Fmmm) R-RII (R3 h m) R-RII (R3 h m) R-RII (R3 h m) L L L L L L L L L

334.2 335.2 336.3 337.3 338.3 339.3 340.4 341.4 342.4 343.4 344.4 345.5 346.5 347.5 348.5 349.6 350.6 351.6 352.6

T

Τ H293.4

T

kJ‚mol-1 phase 119.6 120.5 121.4 122.3 123.2 124.1 125.0 125.9 126.9 127.8 128.7 129.7 130.7 131.6 132.5 133.5 134.5 135.4 136.4


K 353.6 354.7 355.7 356.7 357.7 358.8 359.8 360.8 361.8 362.9 363.9 364.9 365.9 366.9 368.0 369.0 370.0 371.0 372.1

Τ H293.4

T

kJ‚mol-1 phase 137.3 138.3 139.2 140.2 141.1 142.1 113.3 143.1 144.0 145.0 145.8 146.8 147.8 148.8 149.8 150.8 151.8 152.8 153.7


K 373.1 374.1 375.1 376.2 377.2 378.2 379.2 380.2 381.3 382.3 383.3 384.3 385.4 386.4 387.4 388.4 389.5 390.5 391.5

Τ H293.4

kJ‚mol-1 phase 154.7 155.6 156.6 157.5 158.5 159.5 160.5 161.5 162.4 163.4 164.4 165.4 166.4 167.4 168.4 169.4 170.4 171.4 172.4


Journal of Chemical and Engineering Data, Vol. 48, No. 3, 2003 503 T Table 12. Thermodynamic Data of C26: Temperature (T ( 0.5)/K; Enthalpy Values Referred to 293.4 K (H293.4 /kJ‚mol-1; % diff: 1.5%); Phase Name

T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.6 308.7 309.7 310.7 311.7 312.8

0.0 0.7 1.3 2.0 2.6 3.2 3.9 4.6 5.2 5.9 6.6 7.3 7.9 8.6 9.3 10.0 10.7 11.4 12.1 12.7

T

Τ H293.4

phase

K

kJ‚mol-1

phase

K

γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) h) γ0 (P1 γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h)

313.8 314.8 315.8 316.8 317.9 318.9 319.9 320.9 322.0 323.0 324.0 325.0 326.0 327.0 328.1 329.1 330.1 331.2 332.2 333.2

13.5 14.2 14.9 15.5 16.3 17.0 17.7 18.5 19.2 19.9 20.7 21.6 44.3 59.1 60.7 73.8 124.3 125.1 126.0 126.9

γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) γ0 (P1 h) R-RII (R3 h m) R-RII (R3 h m) R-RII (R3 h m) R-RII (R3 h m) L L L L L

334.2 335.3 336.3 337.3 338.3 339.3 340.4 341.4 342.4 343.4 344.5 345.5 346.5 347.5 348.5 349.6 350.6 351.6 352.6

T

Τ H293.4

T

kJ‚mol-1 phase 127.7 128.6 129.4 130.2 131.0 131.9 132.7 133.5 134.3 135.1 135.9 136.8 137.5 138.3 139.0 139.7 140.5 141.2 141.9


K 353.7 354.7 355.7 356.7 357.7 358.8 359.8 360.8 361.8 362.9 363.9 364.9 365.9 366.9 368.0 369.0 370.0 371.0 372.1

Τ H293.4

T

kJ‚mol-1 phase 142.6 143.3 144.1 144.8 145.5 146.2 146.9 147.7 148.4 149.2 149.9 150.6 151.3 152.0 152.8 153.5 154.4 155.2 156.0


K 373.1 374.1 375.1 376.2 377.2 378.2 379.2 380.2 381.3 382.3 383.3 384.3 385.4 386.4 387.4 388.5 389.5 390.5 391.5

Τ H293.4

kJ‚mol-1 phase 156.7 157.5 158.2 159.0 159.8 160.6 161.4 162.2 163.0 163.7 164.5 165.3 166.0 166.8 167.5 168.3 169.1 169.9 170.6


T Table 13. Thermodynamic Data of C27: Temperature (T ( 0.5)/K; Enthalpy Values Referred to 293.4 K (H293.4 /kJ‚mol-1; % diff: 1.5%); Phase Name

T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.6 308.7 309.7 310.7 311.8 312.8

0.0 0.8 1.5 2.3 3.1 3.9 4.7 5.5 6.3 7.1 7.9 8.7 9.6 10.4 11.2 12.1 13.0 13.9 14.8 15.7

T

Τ H293.4

phase

K

kJ‚mol-1

phase

K

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β′0 (Pbcm)

313.8 314.8 315.8 316.9 317.9 318.9 319.9 321.0 322.0 323.0 324.0 325.0 326.1 327.1 328.1 329.1 330.1 331.2 332.2 333.2

16.6 17.5 18.4 19.4 20.3 21.3 22.6 24.6 25.7 28.6 28.6 30.0 51.7 61.0 62.9 64.5 66.1 67.9 136.8 137.9

β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) RIV RIV RIV RIV RIV RIV L L L

334.3 335.3 336.3 337.3 338.3 339.3 340.4 341.4 342.4 343.5 344.5 345.5 346.5 347.5 348.6 349.6 350.6 351.6 352.7

T

Τ H293.4

T

kJ‚mol-1 phase 138.9 140.0 141.0 142.1 143.1 144.2 145.2 146.3 147.3 148.4 149.5 150.5 151.6 152.6 153.7 154.7 155.8 156.8 157.8


K 353.7 354.7 355.7 356.8 357.8 358.8 359.8 360.9 361.9 362.9 363.9 365.0 366.0 367.0 368.0 369.0 370.0 371.1 372.1

Τ H293.4

T

kJ‚mol-1 phase 158.8 159.9 160.9 161.9 163.0 164.1 165.2 166.4 167.5 168.6 169.7 170.8 171.9 173.0 174.1 175.3 176.3 177.5 178.6


K 373.1 374.2 375.2 376.2 377.2 378.2 379.3 380.3 381.3 382.4 383.4 384.4 385.4 386.5 387.5 388.5 389.5 390.6 391.6

Τ H293.4

kJ‚mol-1 phase 179.7 180.8 181.9 183.0 184.1 185.2 186.4 187.5 188.7 189.9 191.0 192.1 193.3 194.4 195.5 196.6 197.7 198.9 200.1



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.6 308.7 309.7 310.7 311.7 312.8

0.0 0.7 1.5 2.2 2.9 3.7 4.3 5.1 5.8 6.5 7.2 8.0 8.7 9.4 10.1 10.9 11.7 12.5 13.3 14.0

T

Τ H293.4

phase

K

kJ‚mol-1

phase

K

δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a)

313.8 314.8 315.8 316.9 317.9 318.9 319.9 320.9 321.9 323.0 324.0 325.0 326.0 327.0 328.1 329.1 330.1 331.1 332.2 333.2

14.9 15.7 16.5 17.2 18.0 18.8 19.5 20.3 21.2 22.0 22.8 23.6 24.4 25.3 26.2 27.0 28.0 61.1 66.2 67.9

δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) RIII RIII RIV L

334.3 335.2 336.3 337.3 338.3 339.3 340.4 341.4 342.4 343.4 344.4 345.5 346.5 347.5 348.5 349.6 350.6 351.6 352.6

T

Τ H293.4

T

kJ‚mol-1 phase 122.3 133.3 134.2 135.1 136.0 137.0 137.9 138.8 139.8 140.7 141.7 142.6 143.6 144.5 145.3 146.3 147.2 148.0 148.9


K 353.7 354.7 355.7 356.7 357.7 358.8 359.8 360.8 361.8 362.9 363.9 364.9 365.9 367.0 368.0 369.0 370.0 371.1 372.1

Τ H293.4

T

kJ‚mol-1 phase 149.8 150.6 151.5 152.4 153.3 154.2 155.1 156.8 157.7 158.6 159.5 160.4 161.3 162.2 163.1 163.9 164.8 165.7 166.6


K 373.1 374.1 375.1 376.1 377.2 378.2 379.3 380.2 381.3 382.3 383.3 384.3 385.4 386.4 387.4 388.5 389.5 390.5 391.5

Τ H293.4

kJ‚mol-1 phase 167.5 168.5 169.4 170.4 171.3 172.3 173.2 174.2 175.1 176.1 177.0 178.0 179.0 179.9 180.9 181.8 182.8 183.3 156.8


504



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8

0.0 0.8 1.6 2.3 3.1 3.9 4.7 5.4 6.3 7.1 7.9 8.6 9.5 10.3 11.2 12.0 12.8 13.7 14.5 15.3

T

Τ H293.4

phase

K

kJ‚mol-1

phase

K

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm)

313.8 314.8 315.8 316.9 317.9 318.9 319.9 321.0 322.0 323.0 324.0 325.0 326.1 327.1 328.1 329.1 330.1 331.1 332.2 333.2

16.3 17.1 18.1 19.0 19.9 20.7 21.7 22.6 23.6 24.5 25.5 27.7 29.6 30.6 31.6 32.6 33.8 48.5 67.1 68.8

β0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) β′0 (Pbcm) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) RIII RIII RIII

334.2 335.3 336.3 337.3 338.3 339.3 340.4 341.4 342.4 343.4 344.5 345.5 346.5 347.5 348.5 349.6 350.6 351.6 352.6

T

Τ H293.4

T

kJ‚mol-1 phase 70.5 71.9 85.7 141.0 142.0 142.9 143.9 144.8 145.8 146.7 147.6 148.6 149.5 150.5 151.5 152.4 30.6 31.6 32.6

RIII RIII L L L L L L L L L L L L L L L L L

K 353.7 354.7 355.7 356.7 357.8 358.8 359.8 360.8 361.8 362.9 363.9 364.9 365.9 366.9 368.0 369.0 370.0 371.0 372.1

Τ H293.4

T

kJ‚mol-1 phase 33.8 48.5 67.1 68.8 70.5 71.9 85.7 153.4 154.4 155.3 156.3 157.2 158.2 159.1 160.1 161.0 161.9 162.9 163.7


K 373.1 374.1 375.1 376.1 377.2 378.2 379.2 380.2 381.3 382.3 383.3 384.3 385.3 386.4 387.4 388.4 389.5 390.5 391.5

Τ H293.4

kJ‚mol-1 phase 164.7 165.7 166.6 167.6 168.5 169.5 170.5 171.5 172.4 173.3 174.3 175.2 176.2 177.2 178.2 179.2 180.2 181.2 182.1



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.6 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8

0.0 1.0 2.0 2.9 3.8 4.7 5.6 6.5 7.5 8.4 9.3 10.3 11.3 12.2 13.1 14.0 15.0 15.9 16.9 17.8

T

Τ H293.4

phase

K

kJ‚mol-1


313.8 314.8 315.8 316.9 317.9 318.9 319.9 321.0 322.0 323.0 324.0 325.0 326.0 327.1 328.1 329.1 330.1 331.2 332.2 333.2

18.8 19.7 20.8 21.9 22.9 24.1 25.1 26.2 27.1 28.0 29.0 30.1 31.1 32.2 33.3 34.6 35.9 37.3 39.5 58.2

T

Τ H293.4

phase

K

kJ‚mol-1

δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) RIII RIII

334.2 335.3 336.3 337.3 338.3 339.3 340.4 341.4 342.4 343.4 344.5 345.5 346.5 347.5 348.6 349.6 350.6 351.6 352.6

72.8 81.6 83.8 87.0 117.1 157.3 158.3 159.4 160.4 161.4 162.4 163.4 164.4 165.3 166.2 167.2 168.2 169.1 170.0

phase RIII RIII RIV RIV L L L L L L L L L L L L L L L

T

Τ H293.4

K

kJ‚mol-1

phase

K

353.7 354.7 355.7 356.7 357.8 358.8 359.8 360.8 361.8 362.9 363.9 364.9 366.0 367.0 368.0 369.0 370.0 371.1 372.1

171.0 171.9 172.9 173.8 174.8 175.7 176.7 177.7 178.7 179.7 180.6 181.6 182.5 183.5 184.4 185.4 186.4 187.4 188.4


373.1 374.1 375.2 376.2 377.2 378.2 379.3 380.3 381.3 382.3 383.3 384.4 385.4 386.4 387.5 388.5 389.5 390.5 391.6

T

Τ H293.4

kJ‚mol-1 phase 189.4 190.3 191.3 192.3 193.2 194.3 195.3 196.3 197.3 198.4 199.5 200.5 201.6 202.7 203.8 204.8 205.9 207.1 208.2



T

Τ H293.3

K

kJ‚mol-1

293.3 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8 313.8 314.8 315.8 316.9 317.9 318.9

0.0 0.8 1.6 2.4 3.2 4.0 4.8 5.6 6.4 7.3 8.1 9.0 9.8 10.7 11.6 12.5 13.3 14.2 15.0 15.9 16.9 17.8 18.7 19.6 20.6 21.6

T

Τ H293.3

phase

K

kJ‚mol-1

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm)

319.9 320.9 322.0 323.0 324.0 325.0 326.0 327.1 328.1 329.1 330.1 331.2 332.2 333.2 334.2 335.2 336.3 337.3 338.3 339.3 340.4 341.4 342.4 343.4 344.4 345.5

22.6 23.7 24.7 25.7 26.7 27.7 28.7 29.8 31.5 34.2 35.4 36.6 37.7 38.9 40.1 41.6 78.1 80.3 82.3 84.2 104.5 159.1 160.2 161.3 162.4 163.5

T

Τ H293.3

phase

K

kJ‚mol-1

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) RIII RIII RIII RIII RIII L L L L L L

346.5 347.5 348.5 349.5 350.6 351.6 352.6 353.6 354.7 355.7 356.7 357.7 358.8 359.8 360.8 361.8 362.9 363.9 364.9 365.9 366.9 368.0 369.0 370.0 371.1

164.7 165.8 166.9 168.0 169.1 170.2 171.3 172.3 173.4 174.5 175.7 176.9 178.0 179.1 180.1 181.1 182.2 183.3 184.4 185.6 186.6 187.7 188.8 189.8N 190.8

T

Τ H293.3

phase

K

kJ‚mol-1

phase

K

L L L L L L L L L L L L L L L L L L L L L L L L L

372.1 373.1 374.1 375.2 376.2 377.2 378.2 379.3 380.3 381.3 382.3 383.4 384.4 385.4 386.4 387.5 388.5 389.5 390.5 391.6 392.6 393.6 394.7 395.7 396.7

191.8 193.0 194.1 195.3 196.4 197.6 198.8 200.0 201.1 202.3 203.4 204.5 205.8 207.0 208.2 209.4 210.6 211.7 212.9 214.1 215.3 216.4 217.6 218.7 219.9


397.7 398.8 399.8 400.8 401.9 402.9 403.9 405.0 406.0 407.0 408.0 409.1 410.1 411.2 412.2 413.2 414.2 415.3 416.3 417.3 418.3 419.4 420.4 421.4 422.5

T

Τ H293.3

kJ‚mol-1 phase 221.1 222.3 223.4 224.6 225.7 226.8 228.0 229.3 230.5 231.6 232.8 234.1 235.3 236.5 237.7 238.9 240.1 241.3 242.5 243.6 244.8 246.0 247.2 248.4 249.7



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.4 299.5 300.5 301.5 302.5 303.5 304.6 305.6 306.6 307.6 308.7 309.7 310.7 311.7 312.7

0.0 0.8 1.7 2.5 3.3 4.2 5.0 5.9 6.7 7.6 8.5 9.4 10.3 11.2 12.0 12.9 13.8 14.7 15.6 16.5

T

Τ H293.4

phase

K

kJ‚mol-1


313.8 314.8 315.8 316.8 317.9 318.9 319.9 320.9 321.9 322.9 324.0 325.0 326.0 327.0 328.0 329.1 330.1 331.1 332.1 333.1

17.4 18.3 19.2 20.1 21.0 21.9 22.8 23.7 24.5 25.4 26.3 27.2 28.2 29.3 30.4 31.6 32.8 33.8 35.0 36.1

T

Τ H293.4

phase

K

kJ‚mol-1

phase

K


334.2 335.2 336.2 337.2 338.3 339.3 340.3 341.3 342.4 343.4 344.4 345.4 346.4 347.5 348.5 349.5 350.5 351.5 352.6 353.6

37.3 38.6 39.8 41.3 48.0 85.1 87.1 89.0 114.9 167.2 168.3 169.3 170.4 171.4 172.4 173.4 174.5 175.5 176.5 177.5

δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) RIII RIII RIII RIII L L L L L L L L L L L L

354.6 355.6 356.6 357.7 358.7 359.7 360.7 361.7 362.8 363.8 364.8 365.8 366.8 367.9 368.9 369.9 370.9 372.0 373.0

T

Τ H293.4

T

kJ‚mol-1 phase 178.5 179.5 180.5 181.5 182.6 183.6 184.6 185.7 186.8 187.8 188.8 189.9 190.9 192.0 193.0 194.1 195.1 196.2 197.2


K 374.0 375.0 376.0 377.1 378.1 379.1 380.1 381.2 382.2 383.2 384.2 385.3 386.3 387.3 388.3 389.4 390.4 391.4 392.4

Τ H293.4

kJ‚mol-1 phase 198.2 199.2 200.3 201.4 202.5 203.5 204.6 205.7 206.8 207.9 209.0 210.1 211.2 212.3 213.4 214.6 215.6 216.7 217.8



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8 313.8 314.8 315.9 316.9 317.9 318.9

0.0 1.0 2.0 2.9 3.8 4.7 5.7 6.7 7.6 8.6 9.7 10.7 11.7 12.8 13.9 14.9 15.9 17.0 18.0 19.1 20.2 21.3 22.4 23.5 24.7 25.8

T

Τ H293.4

phase

K

kJ‚mol-1

phase

K

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm)

319.9 321.0 322.0 323.0 324.0 325.0 326.1 327.1 328.1 329.1 330.1 331.2 332.2 333.2 334.2 335.3 336.3 337.3 338.3 339.4 340.4 341.4 342.4 343.5 344.5 345.5

26.9 28.0 29.2 30.3 31.5 32.7 33.9 35.2 36.4 37.7 39.0 40.2 41.6 43.1 44.6 46.1 47.9 50.3 55.6 77.9 85.2 87.2 89.2 93.9 175.5 176.7

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) C (A2) C (A2) C (A2) RIII RIII RIII RIII RIII L L L

346.5 347.5 348.6 349.6 350.6 351.6 352.7 353.7 354.7 355.7 356.8 357.8 358.8 359.8 360.8 361.9 362.9 363.9 364.9 366.0 367.0 368.0 369.0 370.1 371.1

T

Τ H293.4

T

kJ‚mol-1 phase 177.8 179.0 180.1 181.2 182.4 183.5 184.6 185.7 186.8 187.9 189.1 190.2 191.2 192.4 193.6 194.7 195.8 196.9 198.1 199.2 200.3 201.4 202.4 203.5 204.5


K 372.1 373.1 374.2 375.2 376.2 377.2 378.2 379.3 380.3 381.3 382.3 383.4 384.4 385.4 386.4 387.5 388.5 389.5 390.6 391.6 392.6 393.6 394.7 395.7 396.7

Τ H293.4

T

kJ‚mol-1 phase 205.5 206.6 207.7 208.8 209.7 210.7 211.7 212.8 213.8 214.8 215.8 216.9 218.0 219.1 220.1 221.2 222.3 223.4 224.6 225.7 226.8 227.9 228.9 230.0 231.1


K 397.7 398.8 399.8 400.8 401.9 402.9 403.9 404.9 406.0 407.0 408.0 409.1 410.1 411.1 412.2 413.2 414.2 415.3 416.3 417.3 418.4 419.4 420.4 421.5 422.5

Τ H293.4

kJ‚mol-1 phase 232.3 233.3 234.4 235.6 236.7 237.8 238.9 240.0 241.2 242.4 243.6 244.8 246.1 247.3 248.7 250.0 251.4 252.6 253.9 255.3 256.7 258.0 259.3 260.7 262.1



T

Τ H293.4

T

Τ H293.4

K

kJ‚mol-1

phase

K

kJ‚mol-1

phase

K

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8 313.8 314.8 315.8 316.9 317.9 318.9

0.0 0.8 1.6 2.3 3.2 4.0 4.8 5.7 6.6 7.5 8.4 9.3 10.2 11.1 12.0 13.0 13.9 14.9 15.8 16.8 17.8 18.8 19.9 21.1 22.3 23.4

δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a)

319.9 321.0 322.0 323.0 324.0 325.0 326.1 327.1 328.1 329.1 330.1 331.2 332.2 333.2 334.2 335.3 336.3 337.3 338.3 339.4 340.4 341.4 342.4 343.5 344.5 345.5

24.5 25.7 26.8 27.9 29.1 30.2 31.3 32.4 33.6 34.8 36.1 37.4 38.7 40.0 41.4 42.8 44.3 45.9 47.5 49.3 51.2 54.0 90.0 92.3 95.1 111.9

δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) RIII RIII RIII RIII L

346.5 347.5 348.6 349.6 350.6 351.6 352.7 353.7 354.7 355.7 356.7 357.8 358.8 359.8 360.8 361.9 362.9 363.9 364.9 366.0 367.0 368.0 369.0 370.0 371.1

T

Τ H293.4

T

kJ‚mol-1 phase 181.7 182.9 184.0 185.2 186.3 187.4 188.6 189.8 191.0 192.3 193.4 194.6 195.8 197.0 198.1 199.3 200.5 201.7 202.8 204.0 205.2 206.4 207.6 208.8 210.1


K 372.1 373.1 374.1 375.2 376.2 377.2 378.2 379.3 380.3 381.3 382.3 383.4 384.4 385.4 386.5 387.5 388.5 389.5 390.6 391.6 392.6 393.6 394.7 395.7 396.7

Τ H293.4

kJ‚mol-1 phase 211.4 212.6 213.8 215.0 216.2 217.5 218.8 220.0 221.2 222.5 223.8 225.1 226.4 227.7 228.9 230.2 231.5 232.8 234.1 235.4 236.6 237.8 239.0 240.2 241.4


T

Τ H293.4

K

kJ‚mol-1

phase

397.7 398.8 399.8 400.8 401.9 402.9 403.9 405.0 406.0 407.0 408.1 409.1 410.1 411.1 412.2 413.2 414.2 415.3 416.3 417.3 418.3 419.4 420.4 421.4 422.5

242.6 243.7 245.0 246.1 247.3 248.5 249.7 250.9 252.1 253.4 254.5 255.8 257.0 258.2 259.4 260.7 261.9 263.2 264.4 265.7 266.9 268.2 269.4 270.7 271.9


506



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8 313.8 314.8 315.8 316.9 317.9 318.9 319.9 321.0 322.0 323.0 324.0 325.0

0.0 0.9 1.8 2.8 3.7 4.6 5.6 6.6 7.6 8.6 9.6 10.6 11.7 12.7 13.7 14.8 15.8 16.9 17.9 19.0 20.2 21.2 22.3 23.5 24.5 25.6 26.8 27.9 29.0 30.1 31.2 32.4

T

Τ H293.4

phase

K

kJ‚mol-1

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm)

326.1 327.1 328.1 329.1 330.1 331.2 332.2 333.2 334.2 335.3 336.3 337.3 338.3 339.3 340.4 341.4 342.4 343.4 344.5 345.5 346.5 347.5 348.6 349.6 350.6 351.6 352.6 353.7 354.7 355.7 356.7 357.8

33.6 34.7 36.0 37.2 38.8 40.4 41.7 43.0 44.3 45.5 46.9 48.2 50.2 53.0 54.9 56.7 58.6 60.7 63.3 98.8 102.6 185.5 192.3 193.6 194.7 195.9 197.0 198.2 199.4 200.6 201.8 203.1

T

Τ H293.4

phase

K

kJ‚mol-1

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) B (Aa) C (A2) C (A2) C (A2) C (A2) C (A2) C (A2) RIII RIII L L L L L L L L L L L L

358.8 359.8 360.8 361.8 362.9 363.9 364.9 365.9 367.0 368.0 369.0 370.0 371.1 372.1 373.1 374.1 375.1 376.2 377.2 378.2 379.2 380.3 381.3 382.3 383.3 384.4 385.4 386.4 387.4 388.5 389.5 390.5

204.3 205.6 206.7 208.0 209.3 210.4 211.7 212.9 214.1 215.4 216.7 217.7 218.9 220.1 221.2 222.2 223.3 224.3 225.4 226.4 227.6 228.6 229.8 231.0 232.1 233.3 234.4 235.4 236.6 237.7 238.9 240.2

T

Τ H293.4

phase

K

kJ‚mol-1

phase

L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L

391.6 392.6 393.6 394.6 395.7 396.7 397.7 398.7 399.8 400.8 401.8 402.8 403.9 404.9 405.9 407.0 408.0 409.0 410.1 411.1 412.1 413.1 414.2 415.2 416.2 417.3 418.3 419.3 420.3 421.4 422.4

241.5 242.8 244.0 245.3 246.5 247.8 249.1 250.3 251.6 252.9 254.1 255.4 256.6 257.9 259.2 260.5 261.8 263.1 264.4 265.7 267.0 268.3 269.6 270.9 272.2 273.6 274.9 276.3 277.6 279.0 280.3

L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L

Table 22. Thermodynamic Data of C36: Temperature (T ( 0.5)/K; Enthalpy Values Referred to 293.4 K ( T /kJ‚mol-1; % diff: 1.5%); Phase Name H293.4 T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8 313.8 314.8 315.9 316.9 317.9 318.9 319.9 321.0 322.0 323.0 324.0 325.0

0.0 1.1 2.1 3.2 4.3 5.3 6.4 7.6 8.7 9.8 11.0 12.2 13.4 14.6 15.7 16.8 18.0 19.2 20.4 21.6 22.9 24.1 25.4 26.5 27.8 29.1 30.3 31.6 32.9 34.2 35.6 37.0

T

Τ H293.4

phase

K

kJ‚mol-1

δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a)

326.1 327.1 328.1 329.1 330.2 331.2 332.2 333.2 334.2 335.3 336.3 337.3 338.3 339.4 340.4 341.4 342.4 343.4 344.5 345.5 346.5 347.5 348.6 349.6 350.6 351.6 352.7 353.7 354.7 355.7 356.7 357.8

38.5 39.9 41.5 43.0 44.7 46.4 48.1 49.9 51.8 53.4 55.0 56.8 58.5 60.5 62.6 64.9 67.4 70.0 73.1 76.9 94.5 118.1 156.1 198.0 199.2 200.5 201.7 203.1 204.3 205.6 207.0 208.4

T

Τ H293.4

phase

K

kJ‚mol-1

δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) δ0 (P21/a) RIII RIII RIII L L L L L L L L L L L L

358.8 359.8 360.8 361.9 362.9 363.9 364.9 366.0 367.0 368.0 369.0 370.0 371.1 372.1 373.1 374.1 375.1 376.2 377.2 378.2 379.2 380.3 381.3 382.3 383.3 384.4 385.4 386.4 387.4 388.4 389.5 390.5

209.7 211.0 212.3 213.6 214.8 216.1 217.3 218.6 219.9 221.1 222.5 223.6 224.7 225.9 227.1 228.2 229.3 230.4 231.5 232.6 233.7 234.8 235.9 237.2 238.3 239.5 240.7 241.8 242.9 244.1 245.3 246.6

T

Τ H293.4

phase

K

kJ‚mol-1

phase


391.5 392.6 393.6 394.6 395.6 396.7 397.7 398.7 399.7 400.8 401.8 402.8 403.9 404.9 405.9 406.9 408.0 409.0 410.0 411.1 412.1 413.1 414.2 415.2 416.2 417.2 418.3 419.3 420.3 421.4 422.4

247.8 249.0 250.1 251.3 252.5 253.7 254.9 256.1 257.3 258.4 259.7 260.9 262.2 263.5 264.8 266.2 267.5 268.9 270.3 271.6 273.0 274.4 275.7 277.1 278.5 279.9 281.3 282.7 284.1 285.5 286.9



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8 313.8 314.8 315.8 316.9 317.9 318.9 319.9 321.0 322.0 323.0 324.0 325.0

0.0 1.0 2.1 3.1 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.1 12.1 13.2 14.2 15.3 16.4 17.5 18.6 19.7 21.0 22.2 23.2 24.5 25.5 26.6 27.8 28.9 30.0 31.2 32.4 33.5

T

Τ H293.4

phase

K

kJ‚mol-1


326.1 327.1 328.1 329.1 330.1 331.2 332.2 333.2 334.2 335.3 336.3 337.3 338.3 339.4 340.4 341.4 342.4 343.5 344.5 345.5 346.5 347.5 348.6 349.6 350.6 351.6 352.7 353.7 354.7 355.7 356.7 357.8

34.8 36.6 37.9 39.2 40.5 41.7 42.9 44.1 45.4 46.7 48.1 49.5 52.6 54.3 56.0 57.7 59.5 61.3 63.2 65.2 67.3 69.6 72.4 109.6 193.5 203.7 205.0 206.4 207.7 209.1 210.4 211.7

T

Τ H293.4

phase

K

kJ‚mol-1

B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) RIII RIII L L L L L L L L L

358.8 359.8 360.8 361.9 362.9 363.9 364.9 365.9 367.0 368.0 369.0 370.0 371.1 372.1 373.1 374.1 375.2 376.2 377.2 378.2 379.2 380.3 381.3 382.3 383.4 384.4 385.4 386.4 387.4 388.5 389.5 390.5

213.0 214.2 215.6 216.9 218.3 219.6 220.9 222.3 223.6 225.0 226.3 227.6 228.8 230.2 231.6 233.0 234.3 235.6 236.9 238.2 239.5 240.8 242.2 243.6 244.9 246.3 247.6 249.0 250.3 251.7 253.0 254.3

T

Τ H293.4

phase

K

kJ‚mol-1

phase


391.6 392.6 393.6 394.6 395.7 396.7 397.7 398.7 399.8 400.8 401.8 402.8 403.9 404.9 405.9 407.0 408.0 409.0 410.0 411.1 412.1 413.1 414.2 415.2 416.2 417.2 418.3 419.3 420.3 421.4 422.4

255.5 256.7 258.0 259.2 260.3 261.7 262.9 264.1 265.3 266.5 267.8 268.9 270.1 271.3 272.6 273.9 275.1 276.3 277.6 278.8 280.1 281.3 282.7 283.9 285.3 286.7 288.0 289.2 290.5 291.8 293.1

L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L


T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8 313.8 314.8 315.8 316.9 317.9 318.9 319.9 321.0 322.0 323.0 324.0 325.0

0.0 1.0 2.0 2.9 3.9 4.8 5.8 6.8 7.9 8.9 9.9 11.0 12.0 13.1 14.1 15.2 16.3 17.5 18.6 19.8 20.9 22.2 23.4 24.6 25.8 26.9 28.1 29.3 30.5 31.7 33.0 34.3

T

Τ H293.4

phase

K

kJ‚mol-1

β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca)

326.1 327.1 328.1 329.1 330.2 331.2 332.2 333.2 334.3 335.3 336.3 337.3 338.3 339.4 340.4 341.4 342.4 343.5 344.5 345.5 346.5 347.5 348.6 349.6 350.6 351.6 352.6 353.7 354.7 355.7 356.7 357.8

35.5 36.8 38.1 39.3 40.6 42.0 43.4 44.8 46.2 47.7 49.2 50.8 52.4 54.1 55.8 57.6 59.5 61.6 63.8 66.1 68.7 71.7 75.5 81.6 122.0 208.8 210.2 211.5 212.8 214.2 215.5 216.8

T

Τ H293.4

phase

K

kJ‚mol-1

β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) RIII RIII L L L L L L L L

358.8 359.8 360.8 361.8 362.9 363.9 364.9 366.0 367.0 368.0 369.0 370.0 371.1 372.1 373.1 374.1 375.2 376.2 377.2 378.2 379.2 380.3 381.3 382.3 383.4 384.4 385.4 386.4 387.5 388.5 389.5 390.6

218.1 219.4 220.8 222.1 223.4 224.8 226.1 227.5 228.8 230.2 231.5 232.8 234.2 235.5 236.8 238.2 239.5 240.8 242.1 243.5 244.8 246.1 247.5 248.8 250.1 251.5 252.9 254.2 255.6 257.0 258.4 259.7

T

Τ H293.4

phase

K

kJ‚mol-1

phase


391.6 392.6 393.6 394.7 395.7 396.7 397.8 398.8 399.8 400.8 401.9 402.9 403.9 405.0 406.0 407.0 408.0 409.1 410.1 411.1 412.2 413.2 414.2 415.2 416.3 417.3 418.3 419.4 420.4 421.4 422.4

261.1 262.5 263.9 265.4 266.8 268.2 269.6 271.0 272.4 273.8 275.2 276.6 278.0 279.5 280.9 282.4 283.9 285.3 286.7 288.2 289.7 291.1 292.6 294.0 295.5 297.0 298.5 300.0 301.5 303.0 304.6


508



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.7 312.8 313.8 314.8 315.8 316.9 317.9 318.9 319.9 320.9 322.0 323.0 324.0 325.0

0.0 1.0 2.1 3.1 4.1 5.2 6.3 7.4 8.5 9.5 10.6 11.7 12.8 13.9 15.0 16.2 17.4 18.5 19.7 20.9 22.1 23.3 24.4 25.6 26.8 28.0 29.2 30.4 31.7 32.9 34.2 35.4

T

Τ H293.4

phase

K

kJ‚mol-1


326.0 327.0 328.1 329.1 330.1 331.1 332.2 333.2 334.2 335.2 336.2 337.3 338.3 339.3 340.3 341.3 342.4 343.4 344.4 345.4 346.4 347.5 348.5 349.5 350.5 351.5 352.6 353.6 354.6 355.6 356.6 357.7

36.6 37.9 39.2 40.5 41.8 43.1 44.4 45.8 47.1 48.6 50.0 51.4 52.9 54.4 56.0 57.6 59.2 60.9 62.6 64.5 66.3 68.3 70.3 72.4 74.6 76.8 79.1 81.4 83.9 155.1 220.9 222.4

T

Τ H293.4

phase

K

kJ‚mol-1

β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) β0 (Pbcm) B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) B(Aa) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) RIII RIII L L L L

358.7 359.7 360.7 361.7 362.8 363.8 364.8 365.8 366.8 367.9 368.9 369.9 370.9 371.9 373.0 374.0 375.0 376.0 377.1 378.1 379.1 380.1 381.2 382.2 383.2 384.2 385.3 386.3 387.3 388.3 389.3

223.8 225.2 226.5 227.9 229.2 230.6 231.9 233.4 234.7 235.9 237.2 238.6 239.9 241.3 242.6 243.9 245.2 246.6 247.9 249.2 250.5 251.9 254.6 256.0 257.3 258.7 260.0 261.3 262.8 264.3 265.8

T

Τ H293.4

phase

K

kJ‚mol-1

phase


390.4 391.4 392.4 393.5 394.5 395.5 396.5 397.6 398.6 399.6 400.7 401.7 402.7 403.8 404.8 405.8 406.9 407.9 408.9 410.0 411.0 412.0 413.1 414.1 415.1 416.1 417.2 418.2 419.2 420.3 421.3

267.3 268.7 270.1 271.6 273.2 274.7 276.3 277.8 279.4 281.0 282.6 284.2 285.7 287.3 288.9 290.5 292.1 293.6 295.3 296.8 298.4 300.0 301.6 303.2 304.8 306.5 308.1 309.7 311.4 313.0 314.7


Τ Table 26. Thermodynamic Data of C44: Temperature (T ( 0.5)/K; Enthalpy Values Referred to 298.3 K (H298.3 /kJ‚mol-1; % diff: 1.5%); Phase Name

T

Τ H298.3

K

kJ‚mol-1

298.3 299.4 300.4 301.4 302.4 303.4 304.5 305.5 306.5 307.5 308.5 309.5 310.6 311.6 312.6 313.6 314.7 315.7 316.7 317.7 318.7 319.7 320.8 321.8 322.8 323.8 324.8 325.8 326.9 327.9 328.9 329.9 330.9 332.0

0.0 1.3 2.5 3.7 5.0 6.2 7.4 8.6 9.9 11.2 12.5 13.8 15.2 16.5 17.9 19.3 20.7 22.2 23.5 25.0 26.5 28.0 29.6 31.1 32.7 34.3 36.0 37.6 39.3 41.0 42.8 44.6 46.4 48.2

T

Τ H298.3

phase

K

kJ‚mol-1

β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca)

333.0 334.0 335.0 336.0 337.1 338.1 339.1 340.1 341.2 342.2 343.2 344.2 345.2 346.3 347.3 348.3 349.3 350.3 351.4 352.4 353.4 354.4 355.4 356.5 357.5 358.5 359.5 360.5 361.6 362.6 363.6 364.6 365.7 366.7

50.1 52.0 54.0 56.1 58.3 60.7 63.1 65.8 68.5 71.4 74.0 76.4 78.7 81.2 83.7 86.4 89.1 92.1 95.1 98.4 101.8 105.6 110.2 116.5 127.3 160.9 255.8 257.2 258.7 260.1 261.6 263.0 264.4 265.8

T

Τ H298.3

phase

K

kJ‚mol-1

β0 (Pbca) β0 (Pbca) β0 (Pbca) β0 (Pbca) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) L L L L L L L L L

367.7 368.7 369.8 370.8 371.8 372.8 373.8 374.9 375.9 376.9 377.9 379.0 380.0 381.0 382.0 383.1 384.1 385.1 386.1 387.1 388.2 389.2 390.2 391.2 392.3 393.3 394.3 395.4 396.4 397.4 398.4 399.5 400.5 401.5

267.1 268.5 269.9 271.3 272.7 274.0 275.5 276.9 278.5 280.0 281.3 282.8 284.2 285.8 287.3 288.6 290.0 291.5 293.0 294.4 295.8 297.3 298.7 300.3 301.8 303.3 304.8 306.4 307.9 309.3 310.9 312.4 313.9 315.4

T

Τ H298.3

phase

K

kJ‚mol-1

phase

L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L

402.5 403.6 404.6 405.6 406.7 407.7 408.7 409.8 410.8 411.8 412.8 413.9 414.9 415.9 417.0 418.0 419.0 420.0 421.1 422.1 423.1 424.2 425.2 426.2 427.3 428.3 429.3 430.4 431.4 432.4 433.5 434.5 435.5 436.5

316.9 318.5 320.0 321.6 323.1 324.9 326.7 328.5 330.3 332.1 333.8 335.6 337.4 339.3 341.1 342.9 344.7 346.5 348.3 350.0 351.7 353.4 355.2 357.0 358.8 360.5 362.3 364.2 366.1 367.8 369.6 371.5 373.2 375.0

L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L L


T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.5 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.7 312.8 313.8 314.8 315.8 316.8 317.9 318.9

0.0 1.3 2.7 4.0 5.3 6.6 7.9 9.3 10.7 12.1 13.6 15.1 16.5 17.9 19.4 20.9 22.3 23.7 25.2 26.6 28.1 29.5 31.0 32.5 33.9 35.4

T

Τ H293.4

phase

K

kJ‚mol-1

phase

K

β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21)

319.9 320.9 321.9 323.0 324.0 325.0 326.0 327.0 328.1 329.1 330.1 331.1 332.2 333.2 334.2 335.2 336.2 337.3 338.3 339.3 340.3 341.4 342.4 343.4 344.4

36.9 38.5 39.9 41.4 42.9 44.5 46.0 47.5 49.0 50.5 52.1 53.8 55.3 57.0 58.8 60.5 64.2 64.2 66.3 68.8 71.1 73.5 76.0 79.0 82.6

β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) C(A2) C(A2) C(A2) C(A2)

345.4 346.5 347.5 348.5 349.5 350.6 351.6 352.6 353.6 354.6 355.7 356.7 357.7 358.7 359.7 360.8 361.8 362.8 363.8 364.9 365.9 366.9 367.9 368.9 370.0

T

Τ H293.4

T

kJ‚mol-1 phase 86.4 89.4 91.5 93.9 96.2 98.5 100.9 103.3 105.9 108.3 110.9 113.5 116.1 118.9 122.6 127.0 259.8 279.3 281.0 282.7 284.4 286.0 287.7 289.4 291.1

C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) L L L L L L L L L L

K 371.0 372.0 373.0 374.1 375.1 376.1 377.1 378.2 379.2 380.2 381.2 382.3 383.3 384.3 385.3 386.4 387.4 388.4 389.4 390.5 391.5 392.5 393.5 394.6 395.6

Τ H293.4

T

kJ‚mol-1 phase 292.7 294.4 296.1 297.7 299.4 301.0 302.7 304.4 306.1 307.7 309.5 311.2 312.8 314.5 316.2 317.9 319.6 321.2 322.9 324.6 326.3 328.0 329.7 331.4 333.2


K 396.6 397.7 398.7 399.7 400.7 401.8 402.8 403.8 404.9 405.9 406.9 408.0 409.0 410.0 411.0 412.1 413.1 414.1 415.2 416.2 417.2 418.2 419.3 420.3 421.3

Τ H293.4

kJ‚mol-1 phase 335.0 336.7 338.5 340.2 341.9 343.7 345.4 347.1 348.9 350.7 352.4 354.2 356.0 357.7 359.5 361.3 363.1 365.0 366.8 368.6 370.5 372.3 374.1 376.0 377.8



T

Τ H293.3

K

kJ‚mol-1

293.3 294.4 295.4 296.4 297.4 298.4 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.6 308.7 309.7 310.7 311.7 312.8 313.8 314.8 315.8 316.9 317.9 318.9

0.0 1.3 2.7 4.1 5.4 6.7 8.1 9.5 11.0 12.3 13.7 15.0 16.3 17.6 18.9 20.4 21.9 23.2 24.6 25.9 27.5 29.0 30.4 31.9 33.3 34.7

T

Τ H293.3

phase

K

kJ‚mol-1


319.9 320.9 321.9 323.0 324.0 325.0 326.0 327.0 328.1 329.1 330.1 331.2 332.2 333.2 334.2 335.2 336.3 337.3 338.3 339.3 340.4 341.4 342.4 343.4 344.4 345.5

36.2 37.7 39.3 40.8 42.3 43.9 45.4 47.0 48.7 50.4 52.2 53.9 55.7 57.6 59.6 61.9 64.4 66.8 69.3 71.4 73.5 75.6 77.7 79.8 81.8 83.9

T

Τ H293.3

phase

K

kJ‚mol-1

β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2)

346.5 347.5 348.5 349.6 350.6 351.6 352.6 353.6 354.7 355.7 356.7 357.7 358.8 359.8 360.8 361.8 362.8 363.9 364.9 365.9 366.9 367.9 369.0 370.0 371.0

85.9 88.1 90.2 92.3 94.5 96.7 98.9 101.2 103.5 105.9 108.2 110.6 113.7 116.0 118.3 120.6 123.0 125.5 129.4 295.2 297.0 298.6 300.3 302.0 303.7

The measurements were carried out by sequential programming of the temperature as a function of the time: (i) the rising temperature period, ti, was set at 200 s and corresponded to a temperature jump equal to T2 - T1 ) 1 K (Figure 2); (ii) the temperature level length, tl, depends on a computer test, checking that the calorimeter signal returned to a constant value, corresponding to a steady state. The Cn’s were obtained from Fluka and had the stated purities reported in Table 1. First the samples were melted in stainless steel crucibles which were sealed before their introduction into the calorimeter cell. Figures 3 and 4 show the enthalpy increment through curves as a function of the increasing temperature, obtained for the even C28 and the odd C29, respectively. The repeatability and the accuracy of temperature and enthalpy measurements were determined by using C18 and C26, for which the experimental

T

Τ H293.3

phase

K

kJ‚mol-1

phase

K

C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) L L L L L L L

372.0 373.1 374.1 375.1 376.1 377.2 378.2 379.2 380.2 381.3 382.3 383.3 384.4 385.4 386.4 387.4 388.5 389.5 390.5 391.5 392.6 393.6 394.6 395.6 396.7

305.4 307.3 309.0 310.9 312.8 314.7 316.6 318.5 320.3 322.1 323.9 325.8 327.7 329.7 331.6 333.5 335.4 337.3 339.1 341.0 342.9 344.8 346.7 348.5 350.4


397.7 398.7 399.8 400.8 401.8 402.9 403.9 404.9 405.9 407.0 408.0 409.0 410.1 411.1 412.1 413.1 414.2 415.2 416.2 417.3 418.3 419.3 420.4 421.4 422.4

T

Τ H293.3

kJ‚mol-1 phase 352.3 354.2 356.1 358.1 360.1 362.0 364.0 365.9 367.9 369.9 371.9 373.9 375.8 377.7 379.7 381.7 383.8 385.9 388.0 390.0 392.0 394.0 396.1 398.1 400.2


enthalpy variations in relation to the temperature were compared with the literature data7,46 (Tables 2 and 3): experimental data are in good agreement with the literature results, and this agreement justifies the experimental method used (percent difference < 1.5%); the accuracy of temperature measurements is equal to (0.5 K. Results The enthalpy (HTT0/kJ‚mol-1; T0 ) 293.4 K or 298.3 K) variations with respect to the temperature are listed for each Cn (from C18 to C38, C41, C44, C46, C50, C54, and C60) in Tables 4-30, where the phase type and the transition temperatures are specified. The temperatures and enthalpies of the order-disorder transition and of the fusion as well as the total enthalpy variation from the order-disorder temperature up to the

510



T

Τ H293.4

K

kJ‚mol-1

293.4 294.4 295.4 296.4 297.4 298.5 299.5 300.5 301.5 302.5 303.6 304.6 305.6 306.6 307.7 308.7 309.7 310.7 311.8 312.8 313.8 314.8 315.9 316.9 317.9 318.9

0.0 1.5 2.7 4.1 5.5 7.1 8.5 10.1 11.7 13.2 14.6 16.1 17.7 19.4 21.0 22.5 24.0 25.7 27.3 28.9 30.5 32.1 33.8 35.4 37.0 38.7

T

Τ H293.4

phase

K

kJ‚mol-1

phase

K


319.9 321.0 322.0 323.0 324.0 325.0 326.1 327.1 328.1 329.1 330.1 331.2 332.2 333.2 334.2 335.3 336.3 337.3 338.3 339.4 340.4 341.4 342.4 343.4 344.5 345.5

40.4 42.1 43.9 45.4 46.9 48.7 50.5 52.3 54.2 56.0 57.9 59.8 61.7 63.5 65.5 67.6 69.6 71.7 73.8 76.0 78.3 80.5 83.0 85.7 88.5 92.2

β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) C(A2) C(A2)

346.5 347.5 348.6 349.6 350.6 351.6 352.7 353.7 354.7 355.7 356.7 357.8 358.8 359.8 360.8 361.9 362.9 363.9 364.9 365.9 367.0 368.0 369.0 370.0 371.1

T

Τ H293.4

T

kJ‚mol-1 phase 98.0 102.5 105.3 108.1 110.8 113.6 116.3 119.1 122.1 124.9 127.8 130.9 134.0 137.1 140.0 142.8 145.8 148.7 151.8 154.8 158.0 162.1 304.7 340.9 342.8

C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) L L L L

K 372.1 373.1 374.1 375.1 376.2 377.2 378.2 379.2 380.3 381.3 382.3 383.3 384.4 385.4 386.4 387.4 388.5 389.5 390.5 391.5 392.6 393.6 394.6 395.7 396.7

Τ H293.4

T

kJ‚mol-1 phase 344.7 346.6 348.6 350.8 352.9 355.0 357.1 359.2 361.3 363.6 365.6 367.8 369.9 372.1 374.1 376.0 378.0 380.1 382.4 384.4 386.4 388.4 390.4 392.4 394.4


K 397.7 398.7 399.8 400.8 401.8 402.9 403.9 404.9 405.9 407.0 408.0 409.0 410.1 411.1 412.1 413.1 414.2 415.2 416.2 417.3 418.3 419.3 420.4 421.4 422.4

Τ H293.4

kJ‚mol-1 phase 396.4 398.6 400.8 402.9 404.9 407.0 409.1 411.2 413.2 415.3 417.5 419.5 421.6 423.6 425.8 427.9 430.0 432.2 434.2 436.3 438.4 440.5 442.7 444.9 447.1



T

Τ H298.3

K

kJ‚mol-1

298.3 299.4 300.4 301.4 302.4 303.4 304.5 305.5 306.5 307.5 308.6 309.6 310.6 311.6 312.6 313.6 314.7 315.7 316.7 317.7 318.7 319.8 320.8 321.8 322.8 323.8 324.9 325.9

0.0 1.7 3.4 5.1 6.7 8.4 10.0 11.7 13.4 15.0 16.7 18.3 19.9 21.5 23.1 24.6 26.3 27.9 29.5 31.1 32.8 34.4 36.0 37.6 39.2 40.8 42.4 44.1

T

Τ H298.3

phase

K

kJ‚mol-1

β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21)

326.9 327.9 328.9 330.0 331.0 332.0 333.0 334.1 335.1 336.1 337.1 338.2 339.2 340.2 341.2 342.2 343.3 344.3 345.3 346.3 347.3 348.4 349.4 350.4 351.4 352.5 353.5

45.7 47.4 49.1 50.8 52.4 54.2 55.9 57.7 59.3 61.2 63.1 65.1 67.1 69.3 71.7 75.0 79.7 81.9 83.8 85.9 87.9 90.1 92.1 94.2 96.4 98.6 100.8

T

Τ H298.3

phase

K

kJ‚mol-1

β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) β0 (Pca21) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2)

354.5 355.5 356.6 357.6 358.6 359.6 360.6 361.7 362.7 363.7 364.7 365.8 366.8 367.8 368.8 369.8 370.9 371.9 372.9 373.9 375.0 376.0 377.0 378.0 379.1 380.1 381.1

103.0 105.2 107.6 110.0 112.2 114.5 116.6 119.0 121.3 123.7 126.1 128.6 131.3 134.3 137.5 141.5 146.9 158.4 233.3 339.6 341.7 344.0 346.2 348.5 337.8 340.1 342.3

fus melting temperature (∆HTTo-d .) are reported in Table 31 and compared to literature data.84 The experimental results are in agreement with those of the literature,84 especially for the Cn’s whose carbon atom numbers are lower than or equal to 26. For the Cn’s, whose carbon atom numbers are higher than 26, the experimental results are slightly higher than those of the literature (Figure 5, Table 31); however, the literature data of those Cn’s are determined by differential thermal analyses, using a continuous mode of temperature programming. In this last case, it is more difficult to determine with accuracy the baseline of the calorimetric signal in the course of the solid-solid or solidliquid transitions. Moreover, for the heavy Cn’s (n > 40), a higher enthalpy consumption in relation to that of light Cn’s is observed, certainly due to the progressive appear-

T

Τ H298.3

phase

K

kJ‚mol-1

phase

K

C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) C(A2) L L L L L L L L L

382.1 383.2 384.2 385.2 386.2 387.3 388.3 389.3 390.4 391.4 392.4 393.4 394.5 395.5 396.5 397.5 398.6 399.6 400.6 401.7 402.7 403.7 404.8 405.8 406.8 407.8 408.9

344.5 346.8 349.0 351.3 353.5 355.7 358.0 360.2 362.5 364.8 367.0 369.3 371.5 373.8 376.0 378.3 380.6 382.8 385.0 387.2 389.5 391.7 393.9 396.0 398.3 400.5 402.7


409.9 410.9 411.9 413.0 414.0 415.0 416.1 417.1 418.1 419.2 420.2 421.2 422.3 423.3 424.3 425.3 426.4 427.4 428.4 429.5 430.5 431.5 432.6 433.6 434.6 435.7 436.7

T

Τ H298.3

kJ‚mol-1 phase 405.0 407.2 409.5 411.7 413.9 416.2 418.5 420.8 423.1 425.4 427.8 430.1 432.4 434.6 436.9 439.2 441.4 443.7 446.0 448.2 450.5 452.8 455.0 457.3 459.6 461.9 464.2


ance of a higher quantity of conformation defects75 in the course of the heating. fus enthalpy variations from the To-d orderThe ∆HTTo-d disorder transition temperature up to the Tfus melting temperature are shown in Figure 5, where the mean values of the literature84 and the new experimental data are also shown. All these values increase linearly with respect to the nc carbon atom number from nc ) 4 to nc ) 60 in a manner independent of the nc parity. fus enthalpy The linear equation of the variations of ∆HTTo-d values as a function of the nc carbon number is established by linear least-squares fitting, and the result is as follows: fus 4 e nc e 60: ∆HTTo-d /kJ‚mol-1 ) 4.10nc - 10.98

Journal of Chemical and Engineering Data, Vol. 48, No. 3, 2003 511 Table 31. Comparison of Transition Enthalpy between the Experimental Results and the Mean Values of the Literature83 (lit.)a melting nc.

molar mass

18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 41 44 46 50 54 60

254.50 268.53 282.55 296.58 310.60 324.63 338.66 352.69 366.71 380.74 394.77 408.79 422.82 436.85 450.87 464.90 478.93 492.95 506.98 521.01 535.03 577.11 619.20 647.25 703.36 759.46 843.62

order/disorder

total

Tfus(lit.)83

Tfus

∆fusH(lit.)83

∆fusH

To-d(lit.)83

To-d

∆Ho-d(lit.)83

∆Ho-d

∆Htot(lit.)83

∆Htot

K

K

kJ‚mol-1

kJ‚mol-1

K

K

kJ‚mol-1

kJ‚mol-1

kJ‚mol-1

kJ‚mol-1

301.2 304.9 309.5 313.2 316.8 320.4 323.6 326.3 329.2 331.7 334.2 336.2 338.2 341.1 342.5 344.3 345.6 347.7 348.9 349.8 351.7 354.8 358.7 360.7 365.2 368.1 372.4

300.2 303.7 308.7 312.6 314.9 319.9 323.0 324.7 328.9 331.2 333.2 336.0 337.5 340.0 341.9 343.4 345.3 346.5

61.3 45.6 69.7 47.7 48.8 53.1 54.4 57.1 60.0 61.1 65.1 68.2 68.3

61.5 44.5 73.5 47.5

b 295.5 b 305.6 315.2 315.6 320.7 320.3 326 326.3 330.5 330.8 332.2 336.5 337.2 340.9 342.2 344.2 347 348.8 350.2

294.4

13.7

11.8

304.4 314.9 312.8 319.9 318.8 325.0 325.0 330.1 330.3 332.1 335.2 338.0 337.9 341.1 344.2 346.1 349.0 349.9 354.3

16.3 29.0 21.7 31.7 26.7 33.8 26.8 35.1 30.8 37.0

16.6

61.3 65.5 69.7 73.0 77.6 82.5 88.3 90.7 97.5 96.6 102.2 103.8 108.9

61.5 66.5 73.5 75.8 80.5 86.5 92.4 92.8 100.6 107.6 104.7 106.9 118.9 117.4 126.5 125.8 137.0 136.4 136.1 140.0 146.5 149.2 167.3 180.5 191.6 216.2 225.3

75.8 79.5 79.4 86.3 87.7

52.9 57.2 58.7 61.4 68.9 63.5 67.8 69.8 73.3 77.0 80.7 84.5 86.4

133.2 358.0 360.7 364.9 368.0 372.0

149.6 176.0 162.4 193.2

143.1 156.6 167.1 177.2 204.1

357.7

40.8 31.2 48.0 41.1 31.1

22.4 29.9 28.6 36.5 29.5 36.9 33.0 40.8 36.6 44.2 37.9 45.4 44.1

134.0 133.2

18.2

167.8 176.0 171.1 193.2

a T -1 (% diff: 3%), temperature and enthalpy of fusion; T -1 (% diff: 3%), fus ((0.5)/K and ∆fusH/kJ‚mol o-d ((0.5)/K and ∆Ho-d/kJ‚mol fus fus ) ∆Ho-d + ∫TTo-d Cp dT + ∆fusH/kJ‚mol-1 (% diff: 3%). b No solid/ temperature and enthalpy of order-disorder transition; ∆Htot ) ∆HTTo-d solid transition.

54, and 60). These new thermodynamic data will enable us to establish new predictive models about the behavior of multi-Cn mixtures and solid-liquid equilibria of crude oil cuts.

Notation Crystallographic Structure Ordered Phases of n-Alkanes at “Room Temperature”

fus Figure 5. ∆HTTo-d variations in relation to the carbon atom fus fus ) ∆Ho-d + ∫TTo-d Cp dT + ∆fusH number of the Cn chain: ∆HTTo-d (Figures 3 and 4).

fus with a standard deviation σ ) 2.3 kJ‚mol-1 and ∆HTTo-d ) Tfus ∆Ho-d + ∫To-d Cp dT + ∆fusH.

Conclusion The calorimetric measurement method, using a discontinuous mode of temperature programming, allows us to determine the enthalpy variations with respect to the increasing temperature in the thermodynamic equilibrium state. For the light Cn’s (18 e n e 26), the experimental results are in agreement with those of the literature and justify the measurement method for the thermodynamic data variations of heavier Cn’s (27 e n e 38, 41, 44, 46, 50,

β0(C2p+1) ) orthorhombic phase Pbcm of odd-numbered C2p+1 (nc ) 2p + 1) h of even-numbered C2p (nc ) γ0(C2p) ) triclinic phase P1 2p e 26) δ0(C2p) ) monoclinic phase P21/a of even-numbered C2p (28 e nc ) 2p e 36) β0(C2p) ) orthorhombic phase Pbca of even-numbered C2p (38 e nc ) 2p e 44) β0(C2p) ) orthorhombic phase Pca21 of even-numbered C2p (46 e nc ) 2p) Disordered Phases at “High Temperature” β(Fmmm) ) orthorhombic phase; this phase presents the “Rotator” state, called β-RI R-RII ) rhombohedral Rotator phase (R3 h m) RIII ) triclinic disorder phase RIV ) monoclinic disorder phase Thermodynamic Data To-d/K, ∆Ho-d/kJ‚mol-1 ) temperature and enthalpy of the order-disorder transition (o-d transition) Tfus/K, ∆fusH/kJ‚mol-1 ) temperature and enthalpy of the melting (disordered phase f liquid)

512


fus ∆HTTo-d /kJ‚mol-1 ) enthalpy variation from the orderdisorder transition temperature (To-d) to the melting fus temperature (Tfus) (ordered phase f liquid): ∆HTTo-d Tfus ) ∆Ho-d + ∫To-d Cp dT + ∆fusH

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Experimental Enthalpy Increments from the Solid Phases to the Liquid

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