Crystallographic Data-45. Chrysene

Figure 2 is an orthographic projection of a typical tablet from ethyl alcohol. C. Figure 2, Orthographic Projection of Typical! Tablet of Chrysene fro...
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45.

Chrysene

Contributed by JOHN KRC, JR., A m o u r Researoh Foundation of Illinois I n s t i t u t e of Teehnolo~, Cbieago 16, Ill. C

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Structural Formula for Chrysene XCELLENT crystals of cbrysene can he obtained from ethyl alcohol solutions. Rapid crystallization favors the plate hahit, while slow crystsllization favors the tablet or massive form. Figure 1 shows plates of ohrysene from ethyl alcohol. Figure 2 is an orthographic projection of a typical tablet from ethyl dcohol.

E

Figure 2.

Orthographio Projection of Typical Tablet of Chrysene fmm Ethyl Alcohol

Cell Dimensions. a = 25.0 A.;

b = 6.18 A,; c = 8.34

(1).

Formula Weights per Cell. 4. Principal Lines d 11.29 5.99 5.68 4.94 4.77 4.30 4.15 3.76 3.48 3.36 3.24 3.19 3.02 2.903 2,838

Figure 1. Crystalsof CbrysenefromEthyl Alcohol c m s d Nioole

.~

1/11

1 .cQ

Very weak 0.15

0.34 1.00 0.08 0.53 0.21 0.19 0.79 Very weak Very weak Very weak Very weak Very weak

d 2.714 2.627 2.552 2.481 2.351 2.258 2.153 2.090 2.072 2.011 1.944 1.883 1.857 1.741 1.731

1/19 . . Very weak 0.06 Ven weak 0.20 0.05 0.09 0.03

0.07 0.06 0.06

0.m

0.08 Very weak Very weak Very weak

CRYSTALMORPHOLQGY Grystal Syetem. Monoclinic. Form and Habit. Massive or plates lying on orthopinacoid, 100, showing clinodome, l o l l } , and occasionally basal pin%mid, 1001). Axial Ratio. a:b:c = 4.04:1:1.35. Interfacial Angle (not a polar angle). oiiaoii projection an 100 = 73'. Beta Angle. 115.8' (I). Twinning Plane. 100.

OFPICALFROPERTIES

Refractive Indexes (5893 A,; 25" C.). a' = 1.616 f 0.001 (in 100 plane); a = 1.578 * 0.001: P = 1.775 0.005; y = 2.01 ;t 0.02 (edcd. from OL, 8, and ZV). Optic Axial Angles (5893 A,; 25' C.), 2H = 104"; 2V = 84.5 ' (calcd. from 0 and 2 H ) . Dispersion. I > v. Optic Axial Plane. 010. Sim of Double Refraction. Nemtive. Acute Bisectrix. a. Extinction. a A y = 6'in obtuse P ; a A 7 = 10' in obtuse f

u (1). Molecular Refraction (R) (5893 A,; 25' 1.78 * 0.01; R (caled.) = 73.0; R (ohsd.)

q*

'2.). 73.6.

=

=

Figure 3.

X-RAYDIFFRACTION .DATA Space Group. Gh(I ).

Crystals of Chrysene from Fusion and Chrysene Sublimate. Cmsaed Niools

932

A,

933

V O L U M E 23, NO. 6, J U N E 1 9 5 1 Formula Wei&t. 228.27. Density. 1.298 (flotation); 1.307 (x-rayj.

FUSIONDATA. Chrysene meltP a t 260’ C. with slight decompoeition and with considerable sublimation. If cooled slowly lust belew the melting paint or rapidly a t room temperature, it crystallizes as highly birefringent crystals oriented preferentially to give an off-centered Bso interference figure similar to that obtained on the 100 face of chrysene crystals from ethyl alcohol. So polymorphs were observed during this study. Figure 3 qhows rhrysene cwetals from the melt and chrysene sublimate. ACKNOWLEDGM EST

It IY a plutrmre t o acknowledge the a 4 n a n c e of Irene Corvin and Anne Humphreys, who determined the powder x-ray spacing6 and intensitie LITERATLIRE CITED

J. D . I M , J.. and Rohert-.otl ,J & I . . S a t i c r e , 132, 751 (1933)

(1) Beriial,

C O ~ T X I R L T I O NoBf chyatallographrc d n t r ior rill, rectron should be sent to Kalter C. hf&rone, supervisor, .halytical Section, Armour Research k’onndation of the Illinow Imtitrite of Technoloe). Chicago, I11

Physical Methods in Chemical Analysis. WaUer G. Bed, editor. 640 pages. Academic Press, Inc., 125 E m t Volume 11. xii 33rd St., New York 10, N. Y., 1950. Price, $13.50.

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The editor and the authors of the twelve chapters in Volume

I1 of this work have produced a worthy complement to Volume I. Whereas the first volume dealt for the most part with methods based on the interaction of matter and radiant energy, the present volume is concerned with a wider variety of subjecta: chromatography, radioactive tracer techniques, gss analysis by thermal conductivity, vacuum methods, measurement of surface tension and area of .wfaces, magnetic methods, and four types of electrical methods. The aims snd general organization of the material are the same as before. The authors, carefully selected authorities in their reepective fields, have been eminently successful in presenting their mntesial in such a way that the nonexpert in a given field, with a guod background of chemistry and physics, may read with understanding and acquire some degree of familiaritywith the principles m d practice of the varioua physical methods of chemical analysis. Each author discuses the fundamental principles and theoretical basis of his topic, describes apparatus and m a n i p dative technique, indicates known or probable practical spplications, giw considera.tion to the inherent accuracy, the limitations, and the sources of error, and cites pertinent literature references. The volume ie well hound and pruned on good quality paper, with good type. and the illustrations w m to be exceptionally well donr

PAULK. WISTER

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Spectrochemical Analysis. L. H . .ihreiis. xxiv 269 pages. Addison-Wesley Press, Inc , Cambridge 42, Mass., 1950. Price, 110 This authoritative book is devored entirely to the analysis of rocks, soils, minerals, and related materials. The emphasis is laid almost exclusively upon direct current arc methods of sample excitation. It provides a comprehensive discussion of the theoretical principles and practical applications of this phase of emission spectrochemical analysis. In Part I the physical chttractenatics of the direct current arc

are thoroughly discussed. The many factory which affect the intensities of spectrum lines excited in this source are described. Especially well handled is the phenomenon of selective volatiliaation; listing of the methods recommended for minimizing fractional distillation should be very helpful. The mode of operation of spectroscopic buffem and the recommendations given for their selection are well formulated. In Part I1 the author draws upon his wide experience in geochemical analysis for a discussion of methods of determining traces of particular elements in rocks and minerals. One especially useful chapter is dcvoted to methocie for the determination of major constituents. On unnumbered peg- following the text are given t a b l e of wave lengths of the most sensitive lines of the elements, together with the wave lengths of possible interfering elements. Values of the ionization potential of the element and of the excitation pc+ tentials of the most sensitive lines enhance the usefulness of the tables. *4n adequate bibliography is given, although this reviewer would have preferred to see the references in footnote form near the point of reference rather than collected alphabetically by author name at the end of the text. Many of the tables lack captions and thereby lose some of their value out of context NORUS €I. SACNTRIEB

X-Ray Studies on Polymorphism. Tei-Ichi I&. 231 pagea. blaruzen Co., Ltd., P. 0. Box Tokyo Central 605, Tokyo, 1950. Price, $10. One of the most promising signs of the rehabilitation of the highest type of scientific research in Japan after defmt and several years of isolation from inteMectua1 contact with the rest of the world is this book by the distinguished professor of mineralogy of the University of Tokyo. Trained as a student in the Iaboratories of Niggli in Switzerland and of Sir Lawrence Bragg at Cambridge, to both of whom Ito gives warmest appreciation for guiding him into “our beloved science in the making,” he brings to this contribution an expert knowledge of crystal structure analysis. The book is not a text, but a collection of research papers on experimental studies of mineral structures, with a central unifying theme of polyniorphism based on the the& of submicroecopic twinning in cry~tslr;. In 1938 Ito proposed thc theory of twinned space ~ O M P S ,obtained by superimposing a group of operations called a twinning group onto one of the conventional 230 space groups of Schoenflies. Thus adjacent unit cells may be brought into twinned relationships by rotation, reflection, and gliding (echelon, alternate, and complex) while maintaining the homogroup may be geneity of the lattice as :i whole. A twinned identical with one of the 230 Schoenflies groups, but generally it differ8 in the iutroduction of enhanced ymmetry, experimentally indiratpd by extra regularities of x-ray diffraction spectra whirh are not accounted for by usual space group criteria. Honever, symnieti) may also be degraded in some c a ~ e sof twinning by gliding The y)lysymmetric synthesis may take place 011 a smaller scale than the unit cell (intwnnl tninning) or a larger one (twinning en bloc). Ito proceedP to attempt to show these types of twinning 111 the t or groups of niinernlc subjected to depolymorphism ( ~ pairq tailed single cryetd analyses by accepted x-ray diffraction techniques, including two-dimensional Fourier syntheses of electron density contour maps. Examples are eudidymite and epididymite (HSaBeSiBOs), essentially inner twins; the hexagonal feldspai, 0-celeiitn (BaAI&Oa) from which the structwes of monoclinic and triclinic feldspars may be derived ; the orthorhombic pyroxene, enstntite, as a twin of monoclinic diopside instead of an independent species: anthophyllite as a twinned tremolite; zoisite [HCa2(Al,Fe)AI&Ol,l (space group Pn,,,a) derived strictly a> a twinned form of epidote (space group P 2 l / m ) ,

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