2982
Inorg. Chem. 1983, 22, 2982-2992
grouptheoretical calculations showing that from a 2B2gground state transitions would be vibronically allowed only in o; no ?r-vibronic spectrum would be had, since there are no al, or bl, vibrations of the chromophore TiC1204. In terms of orbital angular-overlap parameters, the proposed energy-level scheme suggests that e: and e,' for oxygen are greater than the corresponding parameters for chlorine. The order of the IJ parameters is that expected from the spectrochemical series. While the ordering of the a values is less evident, it agrees with that found for the analogous Cr(II1) complex2 and that proposed earlier by Barton and Slade.I6 It may be worth noting that in the spectra of the three complexes, Cs2TiCl,.4H20, Cs2CrC15.4H20,*and cs3vcl6. 4H20,3 the a spectrum is the stronger in each case. The dichroism is the strongest in the titanium complex and weakest in the chromium complex. The band that appears as a shoulder 2640 cm-l above the 19 220-cm-I band is most probably due to the coupling of an 0-H stretching vibration with the ligand field transition. This vibration notriceably couples only with the upper ligand field state 2Bl,. In the spectra of some crystals there appears to be one or two other components closer to the band maximum. The distances from the maximum are in the range of other water vibrations. So it may be that more than one water vibration is involved in this shoulder. In the analogous chromium and vanadium complexes a similar band appeared associated also with only one of the ligand field bands, but the symmetry of the bands could not be uniquely determined. The separations in the vanadium and chromium complexes were 2890 and 3070 cm-I, re~pectively.~,~ The difference in maxima in the two polarizations is probably related to the differences in the magnitude of the u vi(16) T. J. Barton and R. C. Slade, J . Chem. Soc., Dalron Trans., 650 (1975).
brations that produce the vibronic bands in the two polarizations. The ground state ZE, will be subject to Jahn-Teller distortion. In D4,,' this will become the two Kramers doublets, and E3/2,; the magnitude and order of this splitting are not known. But the selection rules indicate that transitions to all excited spin-orbit states are vibronically allowed from each ground-state component in both polarizations. So the introduction of spin-orbit coupling will not alter the above arguments. An attempt was made to fit the observed spectra to the energies calculated for d' in D4*symmetry. From the best fit obtained for C S , C ~ C ~ , . ~ Hwe ~ Owere , ~ able to assign the spectra of Cs3VCl6.4HZO3by using the same values of the tetragonal parameters, Ds and Dt. Calculation of the energies of the present compound using these same values (Ds= 239 and Dt = 22 cm-I) proved unsuccessful. The tetragonal splitting is calculated to be only 1066 cm-' as compared with the observed value of 4250 cm-'. In the absence of further data, as for example the splitting of the 2T2, (Oh)ground state, no meaningful calculations can be made, since all tetragonal d' formulations contain more than two parameters. Acknowledgment. P.J.M. is grateful to the Research Corp. for a grant for the purchase of the Displex cryogenic refrigerator. M.F.R. thanks the Natural Sciences and Engineering Research Council for operating and equipment grants and is especially grateful to the Atkinson Charitable Foundation and the J. P. Bickell Foundation for grants toward the purchase of the CAD-4 diffractometer. Registry No. C S ~ [ T ~ C I ~ ( H ~ O 86941-16-4. )~]C~~, Supplementary Material Available: Listings of observed and calculated structure factors and anisotropic thermal parameters and an overall packing diagram (9 pages). Ordering information is given on any current masthead page.
Contribution from the Departments of Chemistry, State University of New York at Buffalo, Buffalo, New York 14214, and University of New Orleans, New Orleans, Louisiana 70148
Electronic Structure of Metalloporphyrins. 2.' Experimental Electron Density Distribution of (meso-Tetraphenylporphinato)iron(111) Methoxide CLAUDE LECOMTE,ZascDANA L. CHADWICK,2aPHILIP COPPENS,*Zaand EDWIN D. STEVENS*2b Received November 19, 1982
The crystal structure and experimental electron density distribution of (meso-tetraphenylporphinato)iron(III) methoxide, C4,H3,N40Fe,has been determined from high-resolution single-crystal X-ray diffraction measurements at 100 K. Integrated X-ray intensities were collected with use of Nb-filtered Mo K a radiation to a resolution of (sin @)/A = 1.15 A-'. Averaging 18 142 symmetry-equivalent reflections from two crystals yielded a set of 8033 independent reflections, which were refined by conventional least-squares to R = 4.4%,R, = 5.4%. The iron atom is five-coordinate with the oxygen atom of the methoxide ion coordinated in the axial position at a distance of 1.816 (2) 8,. The iron is displaced 0.48 8, from the plane of the four nitrogens and 0.56 A from the mean porphyrin plane. The 0-C bond of the methoxide is eclipsed with respect to one of the Fe-N bonds. The experimental electron distribution was determined by least-squares refinement including multipole deformation functions ( R = 2.3%,R, = 2.8%). Populations of the deformation functions in the carbon atoms of the porphyrin ligand agree well with those found previously in (meso-tetraphenylporphyrinato)cobalt(II), which suggests transferability of ligand density between complexes. An approximately spherical electron distribution is found at the iron site, and experimental d-orbital occupancies calculated for the iron atom from the deformation populations are consistent with a high-spin Fe( 111) state. However, small but significant deviations from spherical symmetry are observed which, together with observed net atomic charges, have been used to calculate a Mossbauer quadrupole splitting constant of +0.6 (3) mm/s.
Introduction The intense attention that has been devoted to the stereochemistry and electronic structure of metalloporphyrins results (1) Part 1: Stevens, E. D. J. Am. Chem. SOC.1981, 203, 5087. (2) (a) SUNY Buffalo. (b) University of New Orleans. (c) Permanent
address: Faculte des Sciences, Laboratoire de Cristallographie, 54506 Vandoeuvreles Nancy, France. 0020-166918311322-2982$01.50/0
from their wide utilization in biological systems. Iron porphyrins have attracted special interest because of their use as a prosthetic group in many proteins, including myoglobin and hemoglobin. For example, in the cooperative binding of dioxygen in hemoglobin, changes both in the electronic structure and in the stereochemistry at the iron site appear to be responsible for the unique biological behavior, and the detailed mechanism is still not fully u n d e r ~ t o o d . ~ 0 1983 American Chemical Society
Electronic Structure of Metalloporphyrins Table I. Experimental Data Fe(TPP)OCH, formula space group temp, K cell dimensions a, A b, A c, A
P , deg X-ray wavelength, Mo K a l , A d(calcd), g/cm3 d(obsd), g/cm3 abs coeff p , cm-' transmission factors, range scan mode step size, 28, deg scan width, deg scan speed, s/step detector aperture, mm cryst to detector distance, mm take-off angle, deg cryst size, mm
0
10.219 (1) 15.927 (2) 22.345 (3) 111.94 (2) 0.709 30 1.377 (Z = 4) 1.36 (2) 4.86 0.7 7-0.84 8:28 step scans 0.04 28(Ka,)- 1.1 to 28(Ka,) 1.o 5x5 220 3.O 0.25 X 0.47 X 0.45
+ 1.1
Experimental Section Sample Preparation and Data Collection. Fe(TPP)OCH3 was prepared from Fe(TPP)Br and excess piperidine dissolved in CH2C12 and C H 3 0 H . After brief boiling, the solution was allowed to cool. Slow evaporation of the solvents yielded relatively large black crystals and long colorless needles. Crystal structure determination identified the black crystals as Fe(TPP)OCH3, apparently produced by the reaction
+ C H 3 0 H + pip
2;
100 (5)
From structural studies of model compounds and the proteins themselves, many of the stereochemical aspects of the active site in hemoglobin have been e ~ a m i n e d . ~In a recent paper,' we have demonstrated that accurate experimental information on the electronic structure of metalloporphyrins may also be obtained from careful high-resolution X-ray diffraction measurements. These experiments yield a mapping of the electron distribution, which may be directly analyzed to give information on *-bonding in the ring, metal-ligand covalent bonding, and the distribution of d electrons among the orbitals of the metal atom. The last results are confirmed by independent polarized neutron diffraction measurements, which yield complementary information on the electron spin distributi~n.~.~ In this paper, we report the first high-resolution experimental determination of the electron density distribution in an iron porphyrin, (meso-tetraphenylporphinato)iron(III) methoxide, Fe(TPP)OCH,. Future studies will attempt to provide such information on each of the significant oxidation, coordination, and spin states of iron porphyrins.
Fe(TPP)Br
I
-
Fe(TPP)OCH3 + pipH+Br-
A crystal of Fe(TPP)OCH3 was mounted on a Picker FACS-I automatic diffractometer controlled by the Vanderbilt operating system' and cooled to 100 f 5 K with a stream of cold nitrogen gas generated by a locally modified Enraf-Nonius low-temperature device. During measurements, the gas-stream temperature was maintained to within f l K a t a temperature of 100 f 5 K as monitored by a copperanstantan thermocouple. Unit cell dimensions were obtained by least-squares refinement on the observed setting angles of the KO, peaks of 29 centered reflections with 26 > 60'. Scans for systematically absent reflections (h01, I = 2n 1; OkO, k = 2n 1) and
+
+
c
v)
w
-
w E
tw 7
-u.
-3.00
X
3.00
Figure 1. Difference electron density in a plane perpendicular to the porphyrin ring passing through the iron atom and showing a peak corresponding to second fractionally occupied iron site. Contours are plotted a t 0.1 e A-3, intervals, with zero and negative contours shown by dashed lines. comparison of several symmetry-related reflections uniquely established the space group as P 2 ] / c with one iron porphyrin molecule in the asymmetric unit. Crystal data for Fe(TPP)OCH3 and experimental conditions are summarized in Table I. X-ray intensities were obtained with use of a 6:26 step-scan technique. Each reflection was scanned from 26(Kal) - 1.1' to 20(Ka2) 1.1O . The full step-scan profile of each reflection was recorded on magnetic tape and later analyzed to give the integrated intensity and its estimated standard deviation8 Eight standard reflections measured after every 100 reflections showed a slow decline in intensity reaching about 10% after the measurement of 9720 reflections, a t which time data collection was terminated. Linear least-squares fits to the standard reflection intensities were used to correct the data and to calculate the contribution of scaling to the estimated standard deviations, using a method similar to that of McCandlish, Stout, and Andrews? The data were also corrected for absorption by a numerical Gaussian integration over the crystal volume.1° Maximum and minimum transmission factors were 0.84 and 0.77, respectively. Structure Solution and Refiwment. The crystal structure was solved by direct methods (MULTAN"). After several cycles of full-matrix refinement, difference density maps were calculated revealing the positions of all hydrogen atoms including those of the methoxide ion, thus identifying the axial ligand. All of the hydrogens were included in subsequent refinements with isotropic temperature factors, while anisotropic temperature factors were refined for all other atoms. Core, valence, and total X-ray scattering factors were taken from HartreeFock wave functions,12except for hydrogen, for which a contracted scattering factor" was used. Anomalous scattering factors for Fe, 0, N, and C were also inc111ded.l~ Each observation was weighted by w = 1/2(F,),where u(P,)was taken to be the larger of ucald(P)
+
(8)
Blessing, R. H.; Coppens, P.; Becker, P. J . Appl. Crystallogr. 1974, 7, 488.
(3)
McCandlish, L. E.; Stout, G. H.; Andrews, L. C. Acta Crystallogr., Sect. A 1975, A31, 245. (10) Coppens, P.; Leiserowitz, L.; Rabinovich, D. Acta Crystallogr. 1965,
(4)
(11)
(9)
Perutz, M. F. Er. Med. Bull. 1976, 32, 195. Collman, J. P. Acc. Chem. Res. 1977, 10, 265. Drago, R. S.; Corden, B. B. Ibid. 1980, 13, 353. Scheidt, R. W. Acc. Chem. Res. 1977, 10, 339. Jameson, G. B.; Molinaro, F. S.; Ibers, J. A.; Collman, J. p.; Brauman, J. I.; Rose, E.; Suslick, K. S. J . Am. Chem. SOC.1980, 102, 3224. (5) Williams, G. A,; Figgis, B. N.; Mason, R. J. Chem. SOC.,Dalton Trans. 1981, 734. (6) Coppens, P.; Holaday, A.; Stevens, E. D. J . Am. Chem. Soc., in press. (7) Lenhert, P. G. J . Appl. Crystallogr. 1975, 8, 568.
18, 1035.
Germain, G.; Main, P.; Woolfson, M. M. Acta Crystallogr., Sect. A 1971, A27, 368.
"International Tables of X-ray Crystallography"; Kynoch Press: Birmingham, England, 1974; Vol. 4. (13) Stewart, R. F.; Davidson, E. R.; Simpson, W. T. J . Chem. Phys. 1965, (12)
42, 3175.
(14)
Cromer, D. T.; Liberman, D. J . Chem. Phys. 1970, 53, 1891.
2984 Inorganic Chemistry, Vol. 22, No. 21, 1983 Table 11. Data Reductiona (sin @ ) / A range all reflcns 0.00-0.25 0.25-0.50 0.50-0.80 0.80-1.15
R(F)~
0.029 0.021 0.024 0.055 0.1 10
R,(F )c 0.044 0.034 0.037 0.055 0.1 10
+
of high-order reflections. An alternative technique has been applied in which additional parameters are added to the conventional least-squares refinement model which seek to describe the features of the valence electron distribution in terms of a multipole expansion of density function^.^^^^^ In the model used here, the electron density at each atom is described by a sum of atom centered deformation functions P
a Total number of reflections 18 142, with 8033 unique R ( F ) = z i ( ~ -i zP ) ) / ~ ~ ( F ~ R,(F) ~). = reflections. [Ci(Wi(Fil - P , ) ) ’ / C ( w j F i 4 ) ] 1 ’ 2wi ; = liUZ(Fi2).
+
Lecomte et al.
(zi((p)
= (u2count azsale ( 0 . 0 4 ~ 0 ) 2 ) and ~ ~ 2uoM(p) = F;)2)i/2/N for N measurements of symmetry-related reflections. Reflections with both FOw and FaId less than 30 were considered “unobserved” and were not included in the refinement. The conventional refinement converged at R = 0.039 and R, = 0.049 for 6159 symmetry-independent reflections ([(sin @)/A],, = 0.65 A-’). A difference electron density map (Figure 1) calculated by Fourier summation revealed a large residual peak of 1.2 e/A3 at fractional coordinates of x = 0.60, y = 0.84, and z = 0.64, below the molecular plane and about 0.95 A from the iron atom. Since aspherical features of the d-electron density distribution are expected to occur closer to the metal atom (about 0.45 A in CoTPPI), and since the peak is symmetrically located across the porphyrin plane from the iron atom, it has been interpreted as a partial iron atom resulting either from slight disorder in the molecular packing of the type found in Fe(TPP)Clls or possibly from the presence of a small amount of (FeTPP),O impurity,16although it is difficult to see how it could be accommodated in the lattice. Peaks associated with an axial ligand on the partial iron atom are not apparent on the difference map, but a t least one calculated orientation of a methoxide ion with the carbon atom a t x = 0.650, y = 0.936, z = 0.553 results in no intermolecular contacts with either the oxygen or the methyl carbon atom less than 3.5 A. Additional data was then collected on a second crystal. In addition to recollection of data with (sin @)/A < 0.65 A-l, high-order reflections in the range 0.65 < (sin @)/A < 1.15 were also measured. Since most of the high-order reflections are weak, the results of the previous least-squares refinement were used to predict the intensities of higher order reflections and only those reflections with intensities predicted to be greater than 10 times their estimated standard deviations were measured. Data were collected from all four quadrants, yielding a total of 28 376 reflections. These data were processed in the same manner as the fmt set. Unfortunately, the number of usable high-order data was limited by the width of their diffraction profiles. Refinement of the data from the second crystal gave R = 0.047 and R, = 0.058 for 7489 reflections ([(sin @)/A],, = 1.15 A-i). A comparison of refined parameters from the two data sets did not show any significant differences. A final difference map calculated from the second data set revealed an almost identical peak a t the site of the disordered iron atom. The two data sets were then scaled together with use of their least-squares scale factors and merged (18 142 total reflections) and symmetry-related forms averaged to give a final set of 8033 unique reflections. The internal agreement factors are summarized in Table 11. The poor crystal quality and lack of intensity in high-order reflections are responsible for the poor internal agreement at high (sin @/A. A second iron atom with partial occupancy was then included in a conventional least-squares refinement on the merged data set. The sum of the occupancies of both iron sites was constrained to 1.O. The refinement converged at R = 0.044 and R, = 0.054 with a goodness of fit of 1.84. The fractional occupancy of the second iron site was found to be 0.015 (1). In order to calculate deformation maps of the electron density distribution, it is necessary to obtain positional and thermal parameters for the atoms that are free of bias from the aspherical features of the valence electron distribution.l’ This is frequently achieved by refinements in which only high-order data are included, since the scattering is then primarily due to the core electrons.l* In this study, such a technique cannot be used because of the insufficient number
(15) Hoard, J. L.; Cohen, G . H.; Glick, M. D. J . Am. Chem. SOC.1967,89, 1992. (16) Cohen, I. A. J . Am. Chem. SOC.1969,91, 1980. (17) Coppens, P. Acta Crystallogr., Sect. 8 1974,830, 225.
1
where pcoreand pvalencc are spherical Hartree-Fock core and valence densities, the yl, values are spherical harmonic angular functions in real form
R,, = Nr“(‘) exp(-{r)
(2)
where N is a normalization factor and n and { are chosen for each 1 value, as described previously.20 The P,, Plm, K, and K’ values are refinable parameters. Because of the large number of parameters to be optimized in the multipole model, a number of constraints have been imposed on the population parameters. The populations of chemically equivalent atoms have been constrained to be equal. Other population constraints include C,, symmetry for the iron atom, C, symmetry for the oxygen atom, C, symmetry for the nitrogen atoms (mirror plane perpendicular to the pyrrole rings), C, symmetry for the C, and C, carbon atoms , symmetry for (mirror plane in the plane of the pyrrole ring), and C the C, carbon and carbon atoms for the phenyl rings. The multipole expansion was truncated at the octapolar level (1 = 3) for all carbon atoms, and for hydrogen atoms only a monopole and single dipole directed along the H-C bond were included. Since products of d orbitals correspond to density features with hexadecapolar symmetry ( I = 4), these parameters were included for the iron and nitrogen atoms. Three multipole refinements were done, which differ in the model for the electron density near the iron site. The first refinement (refinement I) was an attempt to fit all of the density around the iron site, including the peak on the opposite side of the porphyrin ring, with the density parameters of the iron at a single site. In refinement 11, two iron sites were included with occupancies of 0.985 and 0.015. The d-electron distribution on the iron atom was represented by a HartreeFock radial function with variable K and variable total number of d electrons. No density corresponding to 4s electrons was included. The second iron atom was assumed to be spherical. In refinement 111, two iron sites were included as in refinement 11, but the d-electron density was represented with a Slater type radial function and the 4s-electron density by a Hartree-Fock radial function. The populations of both the 3d and 4s density functions and the K of the 3d density function were varied. Because of the large number of parameters, it was necessary to divide the parameters into several large blocks, which were refined in alternate cycles. Final positional parameters from refinement I1 are listed in Table 111. The corresponding bond distances are tabulated in Table IV and the bond angles in Table V. The multipole parameters from refinements I, 11, and 111 are compared with those of CoTPP in Table VI. Electron Density Maps. The electron deformation density, defined as the difference between the total observed density and the density corresponding to a superposition of neutral, spherical atoms, pobd/,k - ~psphcricplatom, is sensitive to the redistribution of electrons within the molecule as a result of chemical bonding. The deformation density maps presented here correspond to the density of the least-squares multipole deformation model, rather than the observed density, p-/k. They are obtained by Fourier summation of structure factors and therefore contain the effects of series termination and smearing by atomic thermal motion. Structure factors missing from the observed X-ray data are included in the dynamic model density to a resolution of (sin @)/A = 0.85 A-I. Since the model deformation density is not calculated directly from the experimental data, noise in the maps due to statistical errors in the X-rav measurements is absent. The degree ________ (18) Stewart, R. F.; Jensen, L. H. Z Kristallogr., Kristallogeom., Kristallphys., Kristallchem. 1969,128,133. Stevens, E.D.:Hope, H. Acta
~~
Crystallogr., Sect. A 1975,A31, 494. (19) Dawson, B. Proc. R . SOC.London, Ser. A 1967,298,255.Hard, M ; Hirshfeld, F. L. Acra Crystallogr., Sect. B 1975,831, 162. Stewart, R. F. Acta Crystallogr., Secr. A 1976,A32, 565. (20) Hansen, N. K.; Coppens, P. Acta Crystallogr., Secr. A 1978,A34, 909.
Inorganic Chemistry, Vol. 22, No. 21, 1983 2985
Electronic Structure of Metalloporphyrins Table 111. Atomic Fractional Coordinates X
Y
’
atom
X
Y
Z
0.530 68 (3) 0.405 12 (1 3) 0.713 15 (15) 0.611 37 (15) 0.42255 (15) 0.516 15 (15) 0.749 38 (1 8) 0.856 80 (10) 0.886 19 (19) 0.797 45 (18) 0.798 09 (1 8) 0.710 92 (18) 0.71903 (20) 0.625 33 (20) 0.558 60 (19) 0.458 42 (19) 0.396 17 (19) 0.297 32 (21) 0.263 00 (21) 0.34242 (18) 0.340 39 (18) 0.423 41 (18) 0.430 64 (20) 0.526 95 (20) 0.580 81 (18) 0.689 82 (18) 0.904 64 (19) 1.047 42 (22) 1.147 29 (23) 1.105 33 (25) 0.964 72 (25) 0.863 68 (23) 0.420 1 0 (20) 0.513 36 (22) 0.472 80 (23) 0.341 55 (23) 0.248 07 (23) 0.288 15 (22) 0.247 86 (19) 0.274 73 (20) 0.186 03 (22) 0.071 24 (22)
0.827 98 (1) 0.776 56 (8) 0.821 99 (9) 0.727 39 (9) 0.862 36 (9) 0.954 10 (9) 0.875 39 (11) 0.836 81 (11) 0.761 28 (12) 0.751 69 (11) 0.680 87 (11) 0.67063 (11) 0.600 97 (12) 0.61669 (12) 0.695 36 (11) 0.734 83 (11) 0.812 16 (11) 0.85346 (12) 0.927 26 (12) 0.934 04 (1 1) 1.004 37 (11) 1.01366 (11) 1.088 25 (12) 1.074 44 (11) 0.990 54 (1 1) 0.954 08 (1 1) 0.614 OS (12) 0.629 07 (14) 0.567 65 (16) 0.491 36 (15) 0.476 10 (14) 0.537 27 (12) 0.697 15 (11) 0.705 22 (13) 0.679 98 (12) 0.645 27 (12) 0.635 70 (12) 0.662 26 (12) 1.075 78 (11) 1.117 58 (12) 1.181 03 (12) 1.204 66 (12)
0.655 83 (1) 0.683 57 (6) 0.737 05 (6j 0.61962 (7) 0.560 60 (7) 0.679 13 (7) 0.78961 (8) 0.844 24 (8) 0.824 81 (8) 0.758 02 (8) 0.720 94 (8) 0.656 10 (8) 0.616 25 (9) 0.555 80 (9) 0.557 74 (8) 0.504 71 (8) 0.506 82 (8) 0.450 90 (8) 0.470 69 (9) 0.538 87 (8) 0.575 91 (8) 0.641 53 (8) 0.678 80 (9) 0.738 76 (9) 0.739 00 (8) 0.790 92 (8) 0.752 73 (8) 0.766 78 (9) 0.796 79 (10) 0.81306 (10) 0.800 15 (10) 0.769 75 (9) 0.438 90 (8) 0.406 93 (9) 0.342 86 (9) 0.311 04 (9) 0.342 53 (9) 0.406 32 (8) OS41 33 (8) 0.491 99 (9) 0.457 27 (10) 0.471 79 (10)
C(37) C(381
0.043 93 (23) 0.130 78 (211 0.751 13 (19) 0.672 38 (20) 0.733 27 (23) 0.871 83 (21) 0.951 11 (21) 0.890 59 (19) 0.260 79 (24) 0.893 (2) 0.949 (3) 0.787 (2) 0.612 (2) 0.269 (2) 0.196 (2) 0.378 (2) 0.557 (3) 1.073 (2) 1.243 (3) 1.176 (3) 0.937 (3) 0.770 (2) 0.603 (3) 0.531 (2) 0.316 (3) 0.157 (3) 0.226 (2) 0.354 (3) 0.200 (3) 0.011 (2) -0.030 (3) 0.111 (3) 0.572 (2) 0.680 (2) 0.914 (3) 1.044 (2) 0.941 (2) 0.217 (4) 0.221 (4) 0.247 (4) 0.597 (2)
1.16403 (14) 1.099 26 (13) 1.003 01 i i o j 1.019 76 (12) 1.06262 (12) 1.089 31 (12) 1.073 84 (11) 1.030 83 (19) 0.764 46 (17) 0.858 (1) 0.721 (2) 0.553 (1) 0.584 (1) 0.836 (1) 0.968 (1) 1.135 (1) 1.111 (2) 0.682 (1) 0.582 (2) 0.446 (2) 0.422 (2) 0.528 (1) 0.730 (1) 0.687 (1) 0.628 (1) 0.609 (2) 0.656 (1) 1.100 (2) 1.209 (2) 1.249 (1) 1.180 (2) 1.068 (1) 1.003 (1) 1.071 (1) 1.121 (2) 1.094 (1) 1.019 (1) 0.822 (2) 0.743 (2) 0.730 (2) 0.839 (1)
0.52049 (11) 0.554 86 (9) 0.852 17 isj 0.890 17 (9) 0.948 04 (9) 0.968 22 (9) 0.930 89 (9) 0.872 93 (8) 0.651 07 (12) 0.885 (1) 0.849 (1) 0.633 (1) 0.518 (1) 0.409 (1) 0.448 (1) 0.662 (1) 0.776 (1) 0.756 (1) 0.804 (1) 0.833 (1) 0.812 (1) 0.760 (1) 0.430 (1) 0.319 (1) 0.267 (1) 0.323 (1) 0.427 (1) 0.482 (1) 0.423 (1) 0.449 (1) 0.528 (1) 0.587 (1) 0.874 (1) 0.973 (1) 1.006 (1) 0.944 (1) 0.847 (1) 0.640 (2) 0.677 (2) 0.615 (2) 0.636 (1)
atom
Table IV. Bond Distances and Standard Deviations (A) Fe-N I Fe-0 Fe2-N, C4,-H4,
2.0623 (12) 1.8155 (15) 1.98 (2) 0.94 (4)
C,-N, G-C2
1.384 (2) 1.440 (2) 1.350 (3) 1.437 (2) 1.383 (2) 1.401 (3) 1.398 (2) 1.498 (2) 0.90 (2) 0.93 (2)
‘Z43 c344 c4-N
1
C4-C, C,-C,o C,-C21 C2-H2 C3-H, Cz,-Czz c22423
c23-c24 c 2 44
25
c25-c26 26
2I
C2,-H2, CZ3-H2, CZ4-H2, C2,-H2, CZ6-Hz6
1.394 (3) 1.392 (3) 1.382 (4) 1.3 77 (4) 1.397 (3) 1.391 (3) 0.94 (2) 0.96 (3) 1.00 (2) 0.97 (3) 0.91 (2)
Fe-N, Fe-Fe, Fe2-N4 c4 5 -H 45 ‘6”2
C647 c7-C8 C849 c9-N2 c9410 c645
27
I ‘-O
C7-H7 C,-H, c27-c32
-‘
c27428 ‘28
29
c29-c30 c30-c31
c31-c32
C2,-H,, C,,-HZ9 C,,-H,, ‘3 I -H 31 C,,-H,,
Iron-Ligand 2.0978 (16) Fe-N, 0.96 (2) Fe,-N, 2.36 (2) 0 4 4 , 1.00 (3) Porphinato Ring 1.377 (2) C11-N3 1.445 (3) C11-C12 1.356 (2) c12413 1.435 (3) c13414 1.381 (2) c14-N3 1.394 (2) c14-c15 1.399 (2) Cll-c,, 1.499 (2) ‘1S433 1.01 (2) c 12-H 1 2 0.96 (2) 13-H 1 3 Phenyl Groups 1.387 (3) C,,-C,, 1.395 (3) c,4-c33 1.393 (3) c34-c35 1.378 (3) c35-c,, 1.391 (4) c3.5-c,7 1.395 (3) C37438 0.96 (2) C34-H34 0.93 (3) C,,-H,, G6-H 36 0.96 (3) 0.97 (2) C,7-H,7 0.92 (3) C,,-H,,
2.0726 (14) 2.14 (2) 1.393 (2)
1.384 (2) 1.440 (2) 1.348 (3) 1.439 (2) 1.383 (2) 1.398 (3) 1.395 (3) 1.497 (2) 0.92 (2) 0.95 (2) 1.390 (3) 1.401 (3) 1.386 (3) 1.381 (3) 1.382 (4) 1.390 (3) 0.97 (3) 0.93 (3) 0.94 (2) 0.88 (4) 0.95 (3)
Fe-N4 Fez-N, C45-H4,
C16-N4 c16c17
Cl,-% cl8-cl9
c19c20 16 -‘I c20-c39 C17-H17
5
2.0943 (15) 1.84 (2) 0.90 (4)
1.382 (2) 1.437 (3) 1.352 (2) 1.444 (3) 1.380 (2) 1.400 (2) 1.401 (2) 1.495 (2) 0.92 (2) 0.98 (2) 1.397 (3) 1.388 (3) 1.383 (3) 1.385 (3) 1.390 (2) 1.396 (3j 0.99 (2) 0.92 (3) 0.94 (2) 0.94 (2) 0.93 (3)
2986 Inorganic Chemistry, Vol. 22, No. 21, 1983
Lecomte et al.
Table V. Bond Angles and Standard Deviations (deg) Iron-Ligand
N -Fe-N N,-Fe-N, 0,-Fe-N3 O,-C45-H4,
C,-N, -C4 N I -C -C2
c -c2-c, c2-c3-c4 C3-C4-N c3-C4-C5 N , -C4-C5 N,-C,-C20 c20-c1-c2 c4-c5-c21 c6-cSc21
c4-c5-c6
' 2 2-2 '
1
-' 26
c26-czl-c5 c 2 2 - c 2 1 4 5 t2'-
2'
c
22
22'-
-Cz3 -c 24
'23-'24-'25 2 ' 4-'2
3
5
-' 26
87.02 (6) 151.20 (6) 107.24 (6) 111 (2)
N,-Fe-N4 N2-Fe-N4 0,-Fe-N4 0 1 - C 4 5 -H 4 7
105.9 (1) 109.6 (1) 107.3 (1) 107.4 (1) 109.7 (1) 124.0 (1) 126.2 (1) 126.0 (1) 124.4 (2) 117.0 (1) 118.5 (2) 124.4 ( 2 )
C6-N,-C9
'
cS4647 N246-C5
'
N2-C6 -C,
-' c,-c,-c9 -'
6'
7
8
8 '
9-'
10
IO
NZ-c9-C N2C9-C8
-'
c9-clo-cll 9
