Synthesis and structure of multicomponent crystals of fullerenes and metal tetraarylporphyrins

Article abstract of DOI:10.1021/ic011312l

The preparation of fullerene complexes with metal tetraarylporphyrins in the presence of excess ferrocene (Cp₂Fe) results in the formation of new solvent-free and multicomponent molecular crystals. New isomorphous complexes of C₆₀ with PyZnTPP (ZnTPP ≡ zinc 5,10,15,20-tetraphenyl-21H,23H-porphyrinate) and PyCoTPP (CoTPP ≡ cobalt(II) 5,10,15,20-tetraphenyl-21H,23H-porphyrinate) containing Cp₂Fe and the isostructural C₇₀ complex with PyZnTPP have been prepared. The crystal structures of the new layered C₆₀ complexes CoTMPP·C₆₀ (obtained in the presence of Cp₂Fe) and CoTMPP·2C₆₀·3C₇H₈ (obtained in the absence of Cp₂Fe) have been described (CoTMPP ≡ cobalt(II) 5,10,15,20-tetrakis(p-methoxyphenyl)-21H,23H-porphyrinate). Cobalt atoms of the PyCoTPP and CoTMPP molecules are weakly coordinated to C₆₀ with Co···C(C₆₀) distances in the 2.64-2.82 A range, whereas zinc atoms of PyZnTPP, as well as cobalt atoms of the CoTMPP molecules in the solvent-free phase, form only van der Waals contacts with fullerenes. Different packing arrangements in the crystals of fullerene-porphyrin complexes have been discussed.

Full text of DOI:10.1021/ic011312l

Inorg. Chem. 2002, 41, 3638−3646
Synthesis and Structure of Multicomponent Crystals of Fullerenes and
Metal Tetraarylporphyrins
Dmitri V. Konarev,† Andrey Yu. Kovalevsky,‡ Xue Li,‡ Ivan S. Neretin,§ Alexey L. Litvinov,†
,†
Natal’ya V. Drichko,| Yury L. Slovokhotov,§ Philip Coppens,‡ and Rimma N. Lyubovskaya*
Institute of Problems of Chemical Physics RAS, ChernogoloVka, Moscow Region 142432, Russia,
Crystallography Laboratory, Department of Chemistry, State UniVersity of New York at Buffalo,
Buffalo, New York 14260, Institute of Organoelement Compounds RAS, 28 VaViloV St., 117334
Moscow, Russia, and A. F. Ioffe Physical-Technical Institute, St. Petersburg 194021, Russia
Received December 27, 2001
The preparation of fullerene complexes with metal tetraarylporphyrins in the presence of excess ferrocene (Cp2Fe)
results in the formation of new solvent-free and multicomponent molecular crystals. New isomorphous complexes
of C with PyZnTPP (ZnTPP ≡ zinc 5,10,15,20-tetraphenyl-21H,23H-porphyrinate) and PyCoTPP (CoTPP ≡ cobalt(II)
60
5,10,15,20-tetraphenyl-21H,23H-porphyrinate) containing Cp2Fe and the isostructural C complex with PyZnTPP
70
have been prepared. The crystal structures of the new layered C complexes CoTMPP‚C (obtained in the presence
60
60
of Cp2Fe) and CoTMPP‚2C ‚3C H (obtained in the absence of Cp2Fe) have been described (CoTMPP ≡ cobalt(II)
60
7 8
5,10,15,20-tetrakis(p-methoxyphenyl)-21H,23H-porphyrinate). Cobalt atoms of the PyCoTPP and CoTMPP molecules
are weakly coordinated to C with Co‚‚‚C(C ) distances in the 2.64−2.82 Å range, whereas zinc atoms of PyZnTPP,
60
60
as well as cobalt atoms of the CoTMPP molecules in the solvent-free phase, form only van der Waals contacts
with fullerenes. Different packing arrangements in the crystals of fullerene−porphyrin complexes have been discussed.
Introduction
donor molecules19,20 have been obtained and characterized.
Most of these complexes have a neutral ground state, but
further modification can result in the formation of charged
species with conducting and magnetic properties.
Fullerenes can form two-component complexes with S8,
Cp2Fe, ET, TP, DPA,34 and others3,5,6,11 and three- or four-
Molecular complexes of fullerenes1 with organic and
organometallic donors have recently attracted much attention.
More than 100 complexes2-5 with tetrachalcogenafulvalenes,5-8
aromatic hydrocarbons,5,9 amines,5,10 metallocenes,2,3,5,11,12
porphyrins and metalloporphyrins,13-18 and other potentially
* Author to whom correspondence should be addressed. E-mail: lyurn@
icp.ac.ru.
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M.; Lyubovskaya, R. N. J. Chem. Res., Synop. 1997, 442.
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F. Nature (London) 1992, 355, 331.
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M. J. Chem. Soc., Chem. Commun. 1992, 1764.
† Institute of Problems of Chemical Physics, Russian Academy of
Sciences.
‡ State University of New York at Buffalo.
§ Institute of Organoelement Compounds, Russian Academy of Sciences.
| A. F. Ioffe Physical-Technical Institute.
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3638 Inorganic Chemistry, Vol. 41, No. 14, 2002
10.1021/ic011312l CCC: $22.00 © 2002 American Chemical Society
Published on Web 06/12/2002

Fullerene-Metal Tetraarylporphyrin Complex
7000 cm-1 range. Electronic absorption spectra were measured on
a Perkin-Elmer Lambda 19 UV-vis-NIR spectrophotometer in
the 220-3000 nm range (KBr pellets, 1:2000).
Materials. All chemicals were purchased from Aldrich and used
without further purification. Liquids were dried by distillation under
argon over Na/benzophenone for benzene and toluene, P2O5 for
trichloroethylene (C2HCl3), and KOH for pyridine. The solvents
were stored under argon.
component complexes containing solvent molecules.3,5,7-9,13-20
Replacing some of the solvent molecules for another strong
donor or acceptor ones, one can modify electronic states of
the fullerene or donor component, respectively.21,22 For
example, the doping of fullerene complexes with donors D
by alkali metals M results in the formation of three-
component solids D‚(C60-‚nM+) in which a superconducting
phase is observed at Tc up to 26 K.21 Exposure of neutral
C60 complexes with TMDTDM-TTF, DBTTF, and TPDP34
to iodine vapor results in the substitution of the solvent
molecule by iodine, while the organic component is oxidized,
thus forming donor radical cations and In- anions.22a Diffu-
sion of iodine into a solution containing C60 and ET34 yields
Syntheses. All the complexes were obtained by evaporation of
solutions of fullerenes and corresponding metalloporphyrins under
argon during 5-10 days. For the preparation of pyridine-containing
complexes, the solvent was evaporated in the presence of pyridine
vapor (10 mL of pyridine was loaded into a box to be evaporated
in a separate glass). This method was used to obtain 2PyCoTPP‚
C60‚Cp2Fe‚C7H8 (1) and 2PyZnTPP‚C60‚Cp2Fe‚C7H8 (2) from the
toluene solution (30 mL) containing CoTPP or ZnTPP (36 mg,
0.056 mmol), C60 (20 mg, 0.033 mmol), and Cp2Fe (52 mg, 0.28
mmol) at a 2:1:10 molar ratio. The solvent was decanted from the
crystals of 1 and 2 before Cp2Fe precipitated. Then the crystals
were washed with dry acetone (50-60% yield).
2PyZnTPP‚C70‚C2HCl3‚C7H8 (3) was prepared by the same
method from a toluene/trichloroethylene (1:9) solution (3/27 mL)
containing ZnTPP (18 mg, 0.056 mmol) and C60 (20 mg, 0.028
mmol) at a 2:1 molar ratio. The solvent was decanted from the
crystals of 3, which were then washed with dry acetone (60-80%
yield).
-
single crystals of (ET•+‚I3 )C60,22b in which the layers of the
ET•+‚I3- radical cation salt alternate with those of the neutral
C60 molecules.
To introduce potentially donor molecules in a neutral
supramolecular environment, we prepared fullerene com-
plexes with metal tetraarylporphyrins in the presence of an
excess of ferrocene. We report here the preparation of mixed
crystals of fullerenes with Zn and Co tetraarylporphyrinates
in the presence and absence of Cp2Fe. For the first time
fullerene complexes with two donor counterparts,35 namely,
metalloporphyrin and the Cp2Fe molecules, were obtained.
The second donor component, e.g., Cp2Fe, occupies a
position close to that of solvent trichloroethylene molecule
in the crystal structures of the quasi-isomorphous series
2PyZnTPP‚C60‚Cp2Fe‚C7H8, 2PyCoTPP‚C60‚Cp2Fe‚C7H8, and
2PyZnTPP‚C70‚C2HCl3‚C7H8. The crystal structures of the
two other complexes of C60 with CoTMPP, viz. solvent-free
CoTMPP‚C60 (crystallized in a large excess of Cp2Fe) and
solvated CoTMPP‚2C60‚3C7H8 (obtained in the absence of
Cp2Fe) are also reported.
CoTMPP‚C60 (4) was obtained by evaporation of the toluene
solution (30 mL) containing CoTMPP (22 mg, 0.028 mmol), C60
(20 mg, 0.028 mmol), and Cp2Fe (52 mg, 0.28 mmol) at a 1:1:10
molar ratio. The solvent was decanted from the crystals, which were
then washed with dry acetone (60% yield).
CoTMPP‚2C60‚3C7H8 (5) was prepared by evaporation of the
toluene solution (30 mL) containing CoTMPP (22 mg, 0.028 mmol)
and C60 (20 mg, 0.028 mmol) at a 1:1 molar ratio. The crystals of
1-5 are black prisms whose elemental composition was determined
during X-ray analysis.
Experimental Section
Crystal Structure Determination. Crystallographic information
for 1-5 is summarized in Table 1. X-ray diffraction data for 1, 4,
and 5 were collected at 90 K on a Bruker SMART diffractometer
installed at a rotating anode generator (monochromatized Mo KR
radiation, λ ) 0.710 73 Å), while data for 2 and 3 were collected
at 110 K on a Bruker SMART diffractometer with a sealed X-ray
tube (monochromatized Mo KR radiation). In all cases a series of
ω scans with a 0.3° frame width were collected (six scans with
different æ angles for 1, 4, and 5, three scans for 2 and 3). Reflection
intensities were integrated using the SAINT program.23
The SHELXTL program package24 was used for structure
solution and refinement; the latter was performed by full-matrix
least squares on F2 using all data. The ordered non-hydrogen atoms
were refined anisotropically, with the hydrogen atoms (partially
revealed in the difference Fourier maps) “riding” in idealized
positions. Certain groups of atoms, specifically the carbon atoms
of Cp2Fe, disordered carbons of C60 and toluene in 2, and C70 and
solvent molecules in 3, were refined isotropically. For the C70
molecule in 3 all the C-C bonds equivalent under D5h symmetry
were constrained to be equal.
General. IR spectra of the samples (KBr pellets, 1:400) were
recorded on a Perkin-Elmer 1725X spectrophotometer in the 400-
(18) (a) Stevenson, S.; Rice, G.; Glass, T.; Harich, K.; Cromer, F.; Jordan,
M. R.; Craft, J.; Hadju, E.; Bible, R.; Olmstead, M. M.; Maitra, K.;
Fisher, A. J.; Balch, A. L.; Dorn, H. C. Nature 1999, 401, 55. (b)
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S.; Marciu, D.; Dorn, H. C.; Balch, A. L. Angew. Chem., Int. Ed.
2001, 40, 1223.
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J.; Barrett, A. G. M.; Hoffman, B. M. Eur. J. Inorg. Chem. 2000,
593. (b) Eichhorn, D. M.; Yang, S.; Jarrell, W.; Baumann, T. F.; Beall,
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M. J. Chem. Soc., Chem. Commun. 1995, 1703.
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J. Chem. Soc., Chem. Commun. 1999, 193. (b) Croucher, P. D.;
Nichols, P. J.; Raston, C. L. J. Chem. Soc., Dalton. Trans. 1999, 279.
(c) Andrews, P. C.; Atwood, J. L.; Barbour, L. J.; Croucher, P. D.;
Nichols, P. J.; Smith, N. O.; Skelton, B. W.; White, A. H.; Raston, C.
L. J. Chem. Soc., Dalton Trans. 1999, 2927. (d) Andrews, P. C.;
Atwood, J. L.; Barbour, L. J.; Nichols, P. J.; Raston, C. L. Chem.
Eur. J. 1998, 4, 1384.
(21) (a) Otsuka, A.; Saito, G.; Teramoto, T.; Sugita, Y.; Ban, T.; Zakhidov,
A. A.; Yakushi, K. Mol. Cryst., Liq. Cryst. 1996, 284, 345. (b) Otsuka,
A.; Saito, G.; Hirate, S.; Pac, S.; Ishida, T.; Zakhidov, A. A.; Yakushi,
K. Mater. Res. Soc. Symp. Proc. 1998, 488, 495.
(23) SMART and SAINT, Area detector control and integration software,
Version 6.01; Bruker Analytical X-ray Systems: Madison, WI, 1999.
(24) SHELXTL, An integrated system for solVing, refining and displaying
crystal structures from diffraction data, Version 5.10; Bruker Analyti-
cal X-ray Systems: Madison, WI, 1997.
(22) (a) Lyubovskaya, R. N.; Konarev, D. V.; Yudanova, E. I.; Roschupkina,
O. S.; Shul’ga, Yu. M.; Semkin, V. N.; Graja, A. Synth. Met. 1997,
84, 741. (b) Konarev, D. V.; Kovalevsky, A. Yu.; Coppens, P.;
Lyubovskaya, R. N. J. Chem. Soc., Chem. Commun. 2000, 2357.
Inorganic Chemistry, Vol. 41, No. 14, 2002 3639

Konarev et al.
Table 1. Crystal Data for 1-5
1
2
3
4
5
formula
Mr, g‚mol-1
crystal shape
crystal system
space group
a, Å
2PyCoTPP‚C60‚Cp2Fe‚C7H8 2PyZnTPP‚C60‚Cp2Fe‚C7H8 2PyZnTPP‚C70‚C2HCl3‚C7H8 CoTMPP‚C60
CoTMPP‚2C60‚3C7H8
1250.64
black prisms
monoclinic
P21/c
13.984(1)
21.388(2)
18.178(2)
90
96.586(2)
90
5 401.0(9)
4
2499.22
black prisms
monoclinic
C2/c
30.5233(4)
19.5925(2)
19.2515(2)
90
92.067(1)
90
11 505.4(2)
4
1.433
0.48
90.0(1)
62.26
66 603
16 399 (0.074)
10 989
854
0.083
0.268
2512.34
black prisms
monoclinic
C2/c
30.797(2)
19.532(2)
19.312(1)
90
91.861(2)
90
11 611(1)
4
2573.5
black prisms
monoclinic
C2/c
30.763(3)
19.825(2)
20.036(2)
90
92.250(2)
90
12 210(2)
4
1512.34
black prisms
triclinic
P1h
13.1109(7)
15.3467(8)
16.4652(8)
90.617(1)
110.376(1)
96.720(1)
3 079.6(3)
2
b, Å
c, Å
R, deg
â, deg
γ, deg
V, Å3
Z
F
calc, g/cm3
1.434
0.48
110(1)
58.04
1.400
0.49
110(1)
58.03
1.631
0.36
1.538
0.24
µ, mm-1
T, K
90.0(1)
90.0(1)
max 2θ, deg
reflns, measd
unique reflns (Rint
reflns, I > 4σ(I)
params, refined
R(Fo)b [I > 2σ(I)]
60.28
57.48
50 440
14 187 (0.146)
6 851
18 715
13 269 (0.041)
5 717
34 453
72 390
a
)
15 864 (0.059) 12 655 (0.050)
9 011
1058
0.049
0.113
0.892
8 929
911
0.077
0.235
1.058
830
793
0.085
0.111
wR2(Fo )c
0.242
0.333
2
GOF
1.115
0.976
1.048
a Rint ) ∑|Fo - Fo (mean)|/∑[Fo ]. b R(Fo) ) {∑|Fo - Fc|∑Fo. c wR2(Fo ) ) {∑[w(Fo - Fc )]2]/∑[w(Fo )2]}1/2
.
2
2
2
2
2
2
2
linked by noncrystallographic 2-fold axes. The C60 moiety
in 2 has 48 atomic positions common to both orientations,
while disordered positions for the remaining 12 carbon atoms
form a characteristic pattern of “crosses” on the fullerene
sphere. Ferrocene molecules in 1 and 2, determined with a
relatively low precision due to disorder, as well as toluene
and trichloroethylene solvate molecules in 1-3, show no
shortened intermolecular contacts.
In 3, which is generally isostructural to 1 and 2 notwith-
standing a difference in the components, C70 and toluene
molecules are located on inversion centers. Strongly disor-
dered trichloroethylene molecules are located on the 2-fold
axes, like Cp2Fe in 1 and 2 (Figure 2b). Since both C70 and
toluene molecules lack a center of symmetry, the disorder
gives rise to two orientations with identical occupancy. Each
isolated fullerene molecule in 1-3 is surrounded by the two
PyMTPP moieties (where M ) Co or Zn, Figure 2a,b). The
shortest distances between the centers of the neighboring
fullerene molecules are 13.7 Å in 1 and 2 and 14.0 Å in 3.
Figure 1. Different types of fullerene/porphyrin arrangement in 1-5:
2PyCoTPP‚C60‚Cp2Fe‚C7H8 (1); (b) 2PyZnTPP‚C70‚C2HCl3‚C7H8 (3), (c)
CoTMPP‚C60 (4); (d) CoTMPP‚2C60‚3C7H8 (5). Phenyl groups of MTPP
(M ) Zn, Co) are not shown. Only one orientation of disordered C70
molecule of two is shown for 3.
Results
Synthesis. The preparation of fullerene complexes with
porphyrins by evaporation of the solvent containing C60 and
corresponding metalloporphyrin in the presence of a large
excess of Cp2Fe (10-fold molar excess relative to fullerene)
yields unexpected results as compared to the common proce-
dure where no ferrocene was used.14,15 In some cases new
phases of the ferrocene-containing complexes were formed
quantitatively (1, 2), while for 5 a solvent- and ferrocene-
free complex, which is not formed without Cp2Fe, has been
obtained (see Experimental Section). These complexes are
stable in air and do not lose solvent upon storage.
Molecular Packing and Order/Disorder of Fullerene
Molecules in 1-5. Metalloporphyrin-fullerene arrange-
ments in 1-5 are shown in Figure 1. 1 and 2 are isomorphous
and isostructural, with fullerene and toluene molecules being
on inversion centers and Cp2Fe being located on a 2-fold
axis (Figure 2a). The MTPP molecules in 1-3 lie in general
positions. In 1, C60 molecules are ordered, whereas in 2 they
are disordered over two orientations (70:30 occupancy ratio)
The molecular packing in 4 (zigzag chains of C60 spheres
with van der Waals “caps” of CoTMPP) and in 5 (distorted
honeycomb [C60]n layers with interspersed CoTMPP mol-
ecules, stacked with two neighboring fullerene moieties) is
shown in Figures 3 and 4, respectively. The CoTMPP
molecules stacked between two neighboring C60 molecules
occupy a general position in 4 and a center of symmetry in
5 (see Figure 1c,d), giving rise to 1:1 and 1:2 donor-to-
fullerene ratio, respectively. The molecular packing in 5 is
analogous to earlier studied benzene solvate of a C60 complex
with nonmetalated porphyrin H2TPP‚2C60‚4C6H6.15 The C60
moiety is ordered in both CoTMPP complexes, with the
shortest C60‚‚‚C60 distances of 10.20 Å in 4 and 9.86 Å in 5
and the closest intermolecular C‚‚‚C contacts of 3.68 Å (4)
and 3.22 Å (5). A comparison with the C60‚‚‚C60 distance of
25
9.94 Å in pure C60 indicates a somewhat less dense
arrangement of the molecules in 4.
3640 Inorganic Chemistry, Vol. 41, No. 14, 2002

Fullerene-Metal Tetraarylporphyrin Complex
Figure 2. Molecular packing in the isomorphous 2PyCoTPP‚C60‚Cp2Fe‚C7H8 (1) and 2PyZnTPP‚C60‚Cp2Fe‚C7H8 (2) (a) and the isostructural 2PyZnTPP‚
C70‚C2HCl3‚C7H8 (3) (b). Ferrocene molecules in 1 and 2 and trichloroethylene molecules in 3 are marked with dashed circles. Toluene molecule and phenyl
groups of MTPP (M ) Zn, Co) are not shown. Only one orientation of disordered C70 molecule of two is shown for 3.
Figure 3. Molecular packing in CoTMPP‚C60 (4).
Figure 5. Notation of chemically equivalent bonds and bond angles in
metalloporphyrin moiety for Table 2.
macrocyclic porphyrin ligand remain unchanged in 1-5 as
compared to parent porphyrins. The cobalt atom in 1 is
coordinated with pyridine and TPP in a flattened square-
pyramidal manner, deviating by 0.190 Å from the mean plane
of the macrocycle toward the Py ligand. In 2 and 3 the Zn
atom deviates by ca. 0.43 Å out of the plane in the same
direction. The Py ligand in 1-3 deviates by 5-8° from the
normal to the porphyrin plane. It is interesting that the apical
Co-N(Py) distance in 1 (2.154(2) Å) is close to the Zn-
N(Py) distances in 2 and 3 (2.151(4) and 2.133(6) Å). The
Co atoms in 4 and 5 have a square-planar coordination. The
porphyrin ring in 4 has a saddlelike conformation, whereas
in 5 it is planar within 0.04 Å. As shown in a review,30
porphyrin nonplanarity may be caused, among other reasons,
by the effect of an axial ligand and by steric effects. In 1-3
the square-pyramidal coordination of M atom corresponds
well to that found in the related complex with tetra(4-
pyridyl)porphyrin, PyZnTPyP.27 The saddlelike geometry of
Figure 4. Molecular packing in CoTMPP‚2C60‚3C7H8 (5); toluene
molecules and p-methoxyphenyl groups of CoTMPP are not shown.
The closest intermolecular contacts of 3.35-3.45 Å
between toluene molecules in 5 (an ordered one in a general
position and a disordered one in the symmetry center)
correspond to normal van der Waals interaction.
Structure of Metalloporphyrin Moieties. The main
geometric parameters of porphyrin macrocyclic moieties
(Figure 5) for 1-5 and related compounds26-29 are presented
in Table 2. The values of bond lengths and angles in the
(26) Stevens, E. D. J. Am. Chem. Soc. 1981, 103, 5087.
(27) Collins, D. M.; Hoard, J. L. J. Am. Chem. Soc. 1970, 92, 3761.
(28) Hamor, M. J.; Hamor, T. A.; Hoard, J. L. J. Am. Chem. Soc. 1964,
86, 1938.
(29) Byrn, M. P.; Curtis, C. J.; Khan, S. I.; Sawin, P. A.; Tsurumi, R.;
Strouse, C. E. J. Am. Chem. Soc. 1990, 112, 1865.
(30) Shelnutt, J. A.; Song, X.-Z.; Ma, J.-G.; Jia, S.-L.; Jentzen, W.;
Medforth, C. J. Chem. Soc. ReV. 1998, 27, 31.
(25) Burgi, H.-B.; Blanc, E.; Schwarzenbach, D.; Liu, Shengzhong; Lu,
Ying-jie; Kappes, M. M.; Ibers, J. A. Angew. Chem., Int. Ed. Engl.
1992, 31, 640.
Inorganic Chemistry, Vol. 41, No. 14, 2002 3641

Konarev et al.
Table 2. Deviation of Metal Atom from Average Plane of Porphyrin Macrocycle (∆), Selected Bond Distances and Bond Angles in Metalloporphyrin
Moiety,a and Metal-Fullerene Contacts in 1-5 and Related Compounds
1
2
3
4
5
CoTPP26 PyZnTPyPb 27 H2TPP28 H2TPP‚2(m-xylene)29
porphyrin geom planar
planar
0.435
planar
0.433
saddle
0.016
planar
0
saddle
0
planar
0.369
saddle
planar
∆(M), Å
0.190
Bond Lengths, Å
I
II
III
IV
V
1.986(1)
1.375(1)
1.438(1)
1.348(2)
1.392(1)
2.072(2)
1.377(2)
1.446(2)
1.351(4)
1.401(2)
2.075(3)
1.370(3)
1.443(3)
1.349(5)
1.405(3)
1.937(1)
1.380(1)
1.435(1)
1.349(2)
1.392(1)
1.980(1)
1.379(2)
1.437(2)
1.352(3)
1.390(2)
1.948(1)
1.378(1)
1.441(1)
1.361(1)
1.390(1)
2.073(2)
1.369(2)
1.446(2)
1.356(3)
1.409(2)
1.350(5)
1.443(5)
1.361(5)
1.403(5)
1.377(6)
1.431(6)
1.354(8)
1.391(6)
Bond Angles, deg
III
IIII
IIIII
IIIIV
IIV
VV
127.5(1)
104.9(1)
110.7(1)
106.8(1)
125.9(1)
123.0(2)
126.6(1)
106.4(2)
109.6(1)
107.2(2)
125.5(2)
125.8(2)
126.5(1)
106.6(3)
109.6(2)
107.1(2)
125.6(2)
125.5(3)
127.2(1)
127.5(1)
104.9(1)
110.7(1)
106.9(2)
125.9(1)
122.9(2)
127.4(2)
105.1(2)
110.8(2)
106.6(2)
125.6(2)
121.9(2)
126.2(1)
106.6(2)
109.8(2)
106.9(2)
125.9(2)
124.7(2)
105.4(1)
110.1(1)
107.2(1)
125.0(1)
121.8(1)
108.8(4)
108.7(3)
106.9(4)
126.0(4)
125.1(5)
106.1(8)
109.9(6)
107.0(6)
124.6(6)
126.9(8)
M‚‚‚Cn, Å
2.82-3.49 3.07-3.32 3.09-3.46 3.16-3.41 2.64-3.55
a For notations see Figure 5. b TPyP ) tetra(4-pyridyl)porphyrin.
porphyrin moiety in 4 is induced by packing forces, as in
many solvent- and fullerene-free molecular crystals, viz.
CoTPP,26 H2TPP,28 and other porphyrin derivatives.30
Metalloporphyrin-Fullerene Contacts in 1-5. In the
isostructural complexes 1-3 of C60 and C70 with PyMTPP,
fullerene molecules arrange near the metal atoms at the apical
site opposite the Py ligand. Slightly shortened Co‚‚‚C(C60)
contacts in 1 (2.82 and 3.07 Å, Figure 1a) involve two carbon
atoms of the 5-6 bond of C60 which is almost parallel to
the N-Co-N line in the CoTPP molecule. These contacts
are close to the similar contacts found in fullerene complexes
with CoOEP34 (2.67-2.86 Å).13 Unlike 1, all intermolecular
contacts between PyZnTPP and fullerenes in 2 and 3
correspond to typical van der Waals distances, due to a
stronger displacement of the zinc atom toward the pyridine
ligand in the square-pyramidal coordination environment.
The shortest Zn‚‚‚C(fullerene) distance (3.08 Å) is longer
than the corresponding distances in the C60 complexes with
ZnOEP34 (2.94-2.98 Å)13,16 or the C70 complex with ZnTPP
(2.85-2.96 Å).14
All intermolecular Co‚‚‚C(C60) contacts in 4 have typical
van der Waals lengths. The two C60 molecules above and
below porphyrin moiety are located asymmetrically relative
to saddlelike CoTMPP. The shortest Co‚‚‚C(C60) distances
are 3.17 and 3.26 Å with the 6-5 bond of the “A” C60
molecule and 3.40 and 3.68 Å with the 6-6 bond of the
“B” C60 molecule (Figure 1c).
Figure 6. UV-visible absorption spectra of CoTMPP‚2C60‚3C7H8 (5) (a)
and CoTMPP‚C60 (4) (b) in KBr matrix. The arrow shows the position of
the CT band.
C60 or C70 and metal tetraarylporphyrins. The spectra of 1
and 2 also show the bands ascribed to Cp2Fe.
The bands of the F1u(4) vibration of C60 are observed at
1427 cm-1 for 1 and 2 and at 1429 cm-1 for 4 and 5 as
compared to that of parent fullerene at 1429 cm-1. However,
the absorption bands of metalloporphyrins in 1-5 are slightly
shifted (up to 8 cm-1). The position of the Cp2Fe bands in
1 and 2 coincides with that for pure Cp2Fe.
UV-Visible Spectra. The UV-visible spectra of 1-5
are also a superposition of the spectra of the starting
compounds. The spectra of the C60 complexes with CoTMPP
(4 and 5) are shown in Figure 6. The bands at 262 and 339
nm (4) and 261 and 336 nm (5) are ascribed to C60. These
bands are blue shifted up to 8 nm relative to those of parent
C60 (266 and 344 nm). The bands at 433 and 537 nm in 4
and 5 are attributed to the CoTMPP chromophore (Figure
6a,b). These bands are red shifted by up to 7 nm relative to
those of starting CoTMPP (426 and 536 nm). The bands of
ZnTPP and CoTPP in the pyridine-containing complexes (1-
3) show larger red shifts (up to 15 nm) relative to parent
metalloporphyrin.
Unlike 4, the planar CoTMPP molecule in 5 forms
distinctly short Co‚‚‚C(C60) contacts (2.65 and 2.67 Å) with
the two C60 molecules located symmetrically above and
below the porphyrin plane (Figure 1d). These short contacts
complement a square-planar coordination of the Co atom in
CoTMPP to give a square-bipyramidal arrangement with the
centers of the 6-6 bonds of the two neighboring C60
molecules in apical positions. As in 1, the weakly coordinat-
ing C-C bonds of fullerene moieties are parallel to the
N-Co-N line in the CoTMPP molecules.
Additional weak absorption in the visible range with a
maximum at 830 nm in 5 may be evidence of charge transfer
from CoTMPP to the C60 molecule (Figure 6a).
IR Spectra. The IR spectra of the complexes are a
superposition of those of the individual components, namely
3642 Inorganic Chemistry, Vol. 41, No. 14, 2002

Fullerene-Metal Tetraarylporphyrin Complex
Discussion
molecule (distorted squares with diagonals of ca. 7.5 × 6 Å
and a thickness of ca. 3.4 Å), whereas in 1 and 2 the cavity
is large enough to accommodate a bulkier ferrocene molecule
(almost spherical with a diameter of ca. 6.8 Å).
IR and UV-Visible Spectra. Molecular complexes 1-5
differ by their donor-to-fullerene ratio, viz. 2:1 in 1-3 (with
the additional donor component Cp2Fe in 1 and 2, and solvent
molecules in all cases), 1:1 in 4, and 1:2 in 5.
The lack of short van der Waals contacts of guest
molecules in 1-3 is indicative of their “loose” positioning
in the porphyrin-fullerene framework. Such an uncon-
strained van der Waals environment gives rise to disorder
observed for all guest components, including ferrocene (see
Experimental Section). Parallel sandwich conformations of
the Cp2Fe moieties in 1 and 2 are similar to those of pure
ferrocene33 or the ferrocene molecule in 2Cp2Fe‚C60.11
The difference in the Co‚‚‚C60 (in 1) and Zn‚‚‚C(C60) (in
2) distances may be associated with a stronger metal-C60
d-π interaction in the case of cobalt. The shortened Co‚‚‚
C(C60) distances in 1 are accompanied by the ordering of
the C60 molecules (see Figure 1a), while the absence of any
secondary bonding between zinc atoms and fullerenes in 2
and 3 results in rotational disorder in the fullerene molecules
in these complexes (Figure 1b). However, no substantial
changes are observed in the spectra of 1. Thus, higher
ordering may also be a result of better van der Waals fitting
of C60 to MTPP in the Co complex with more flattened
CoTPP environment.
Crystal Structures and Packing in Known Fullerene-
Porphyrin Complexes. Molecular complexes of fullerenes
with porphyrins and metalloporphyrins as a donor component
(D), studied by single-crystal X-ray diffraction, are sum-
marized in Table 3. The main supramolecular characteristics,
defining their composition and properties, are the motif
of fullerene-donor packing and cavities therein, conforma-
tion of the porphyrin macrocycle, shortest intermolecular
contacts of fullerene-porphyrin, and fullerene-fullerene
distances. Special attention is paid here to the existence, or
absence, of disorder of the fullerene molecules, shortest
metal-fullerene distances, and the conformation of a mac-
rocycle.
The IR data (see Results) show only small shifts (up to 2
cm-1) of the F1u(4) vibration, which is the most sensitive to
charge transfer to the C60 molecule,31 providing strong
evidence for the fully van der Waals character of the
complexes. The shifts of the bands of metalloporphyrin
molecules observed in 1-5 seem to be associated with
changes in geometry rather than with charge transfer.
On the formation of 4 and 5, noticeable shifts of both C60
and CoTMPP bands are observed in the UV-visible spectra.
The shifts observed earlier in the spectra of other fullerene
complexes with metal tetraphenylporphyrins15 may be as-
sociated with the interaction of C60 and CoTMPP π-systems.
Larger red shifts of the CoTPP and ZnTPP bands in 1-3
are attributed to additional coordination of pyridine to the
central metal cation of porphyrin. The intensity of charge
transfer bands depends on the efficiency of HOMO-LUMO
overlapping between donor and acceptor molecules. Actually
the charge transfer band is observed only in the spectrum of
5 in which the distances between the porphyrin and C60
molecules are the smallest among 1-5.
Molecular packing and weak intermolecular interactions
in 1-5 together with a detailed analysis of these factors will
be discussed below for all published molecular complexes
of fullerenes with porphyrin counterparts.
Packing and Intermolecular Interactions in 1-5. A
dense packing principle32 applied to molecular complexes
of fullerenes with porphyrins requires a close arrangement
of their spheroid and disklike molecules with little or no voids
in between. Filling the cavities that inevitably exist between
such moieties requires either smaller molecules of solvent
and/or second donor counterpart, or conformational flexibility
of a porphyrin moiety. Both variants are observed in the
complexes under discussion, viz. filling intermolecular
cavities (1-3, 5) and saddlelike conformation of CoTMPP
in the solvent-free 4. Similar saddlelike geometry was
observed earlier in solvent-free porphyrin crystals (see Table
2), whereas H2TPP‚C60‚3C7H814, H2TPP‚2C60‚3C6H6, H2-
TPP‚2C60‚4C6H6, and CuTPP‚C70‚1.5C7H8‚0.5C2HCl3 pre-
pared earlier15 contain almost planar porphyrin molecules
and from one to three solvent molecules per fullerene moiety.
The metalloporphyrin-fullerene frameworks in 1, 2, and
3 have two types of cavities, occupied by different guest
molecules (Figure 1a,b). The cavities of the first type are of
similar size and are occupied by toluene molecules (which
can be described as elongated disks with dimensions of ca.
7.5 × 7 × 3.5 Å). The cavities of the second type are larger
in 1 and 2 than in 3 because of a smaller size of the C60
sphere relative to the C70 ellipsoid. As a result, the cavity of
the second type in 3 is occupied only by trichloroethylene
As a convenient tool which readily reveals errors in
reported composition and/or crystal structures, the packing
coefficient k32 has been calculated for each compound. This
parameter, defined commonly as a fraction of the unit cell
volume occupied by molecules, usually attains 0.70-0.78
in molecular crystals. Thus, an unreasonably high value of
packing coefficient k ) 1.11 for the reported complex
(33) (a) Seiler, P.; Dunitz, J. D. Acta Crystallogr., Sect. B 1979, 35, 1068.
(b) Seiler, P.; Dunitz, J. D. Acta Crystallogr., Sect. B 1979, 35, 2020.
(c) Seiler, P.; Dunitz, J. D. Acta Crystallogr., Sect. B 1982, 38, 1741.
(34) Donor compounds and their abbreviations: H2TPP, 5,10,15,20-tetra-
phenyl-21H,23H-porphyrin; ZnTPP, zinc 5,10,15,20-tetraphenyl-21H,-
23H-porphyrinate; CoTPP, cobalt(II) 5,10,15,20-tetraphenyl-21H,23H-
porphyrinate; CuTPP, copper(II) 5,10,15,20-tetraphenyl-21H,23H-
porphyrinate; CoTMPP, cobalt(II) 5,10,15,20-tetrakis(p-methoxyphenyl)-
21H,23H-porphyrinate; CoOEP, cobalt(II) 3,7,8,12,13,17,18-octaethyl-
21H,23H-porphyrinate; ZnOEP, zinc 2,3,7,8,12,13,17,18-octaethyl-
21H,23H-porphyrinate; ET (BEDT-TTF), bis(ethylenedithio)-
tetrathiafulvalene; Cp2Fe, ferrocene; Py, pyridine; TMDTDM-TTF,
tetramethylenedithio-4,5-dimethyltetrathiafulvalene; DBTTF, diben-
zotetrathiafulvalene; TPDP, 3,3′,5,5′-tetraphenyldipyranilidene; TP,
triphenylene; DPA, 9,10-diphenylanthracene.
(31) Picher, T.; Winkler, R.; Kuzmany, H. Phys. ReV. B 1994, 49, 15879.
(32) Kitaigorodskii, A. I. Organic Crystal Chemistry; Consultants Bu-
reau: NewYork, 1957; p 106.
(35) Everywhere in this paper, we refer to the potential donor components
in the neutral molecular complexes, capable of forming cations under
oxidation, as “donor molecules”.
Inorganic Chemistry, Vol. 41, No. 14, 2002 3643

Konarev et al.
Table 3. Molecular Complexes of Fullerenes/Porphyrins with Known Crystal Structuresa
macrocyclic
donors (D)b
ratio
D/Cn
Cn
M‚‚‚C
conformation
of D
Cn
solventc
order (center‚‚‚C)
k
packing motif according to Figure 7
ref
H2TPP
H2TPP
C60
C60
1/2 1.5C6H6
1/2 2C6H6
-
-
(2.77, 2.86)
(2.67, 2.78)
P
P
0.73 framework [2C60‚D]n, with channels 15
0.74 puckered honeycombs [C60]n,
D in betweeen
15
H2TdMePP
H2TPP
C60
C60
C60
C60
C70
C70
C60
2/3 1.33C7H8
-
-
-
-
-
-
+
n/a
P
P
P
S
P
P
P
0.73 zigzag chains [C60‚D]n + isolated C60 14
1
1
1
1
3C7H8
(2.70, 2.75)
(2.69, 2.88)
n/a
(2.86)
2.99, 3.04
2.65, 2.67
0.75 contacting zigzag chains [C60‚D]n
0.68 zigzag chains [C60‚D]n
0.71 n/a
0.73 linear chains [C70‚D]n
0.75 n/a
14
14
14
14
14
H2TdBuPP
H2TpivPP
H2TdMePP
NiTMePP
CoTMPP
4C7H8
1/2 1C7H8
1/2 1.5C7H8
0.75 puckered honeycombs [C60]n,
D in between
0.77 zigzag chains [C60]n, D in between
0.77 linear chains [C60]n, (D)2 pairs
0.71 zigzag chains [C70]n, D in between
0.61 as above
0.73 zigzag chains [C60]n,
capping D in between
0.74 as above
this workd
CoTMPP
CuTPP
CuTPP
ZnTPP
C60
C60
C70
C70
1
2
+
-
+
+
-
3.17, 3.26
3.42
2.88, 2.90
2.89
S
S
P
P
S
this worke
15
15
14
17
1
1
1
1.5C7H8, 0.5C2HCl3
-
FeTPP+B(C6F5)4 C60
2.5C6H4Cl2
2.63, 3.11
ClFeOEP
PyCoTPP
PyZnTPP
PyZnTPP
CoOEP
CoOEP
ZnOEP
ZnOEP
CoOEP
C60
C60
C60
C70
C60
C60O
C60
C60
1
1CHCl3
-
+
-
-
+
+
+
-
-
3.20
2.82, 3.07
3.08
P
P
P
P
P
P
P
P
P
13
2
2
2
2
1C7H8, 1Cp2Fe
1C7H8, 1Cp2Fe
1C7H8, 1C2HCl3
1CHCl3
0.73 isolated D‚C60‚D groups
0.72 as above
0.70 as above
this workf
this workg
3.08
this workh
2.67, 2.78
2.67, 2.73
2.94, 2.98
2.98
0.74 helices [C60‚2D]n
13
13
13
13
13
2
1CHCl3
0.75 as above
2
1CHCl3
0.75 as above
0.75 as above
1.11 n/a
2
2C6H6
(C60)2O
1
0.4C6H6, 0.6CHCl3
2.67
1/2
1
0.74
CoOEP
C70
1C6H6, 1CHCl3
+
2.80
P
0.77 zigzag chains [C70]n,
capping pairs (D)2 in between
0.76 as above
0.77 as above
0.76 puckered honeycombs [C60]n,
pairs D2 in between
13
NiOEP
CuOEP
CuOEP
C70
C70
C60
1
1
1
1C6H6, 1CHCl3
1C6H6, 1CHCl3
2C6H6
+
+
+
2.83
2.92
3.02
P
P
P
13
13
16
PdOEP
Ru(CO)(OEP)
C60
C60
1
1
1.5C6H6
2C7H8
+
-
3.04, 3.08
2.83
P
P
0.74 as above
16
16
0.75 zigzag chains [C60]n,
capping D in between
0.76 zigzag chains [M3N@C70]n,
capping pairs (D)2 in between
0.76 as above
CoOEP
Sc3N@C80
1
0.5C6H6, 1.5CHCl3
-
2.79
P
18a
CoOEP
CoOEP
ErSc2N@C80
Sc3N@C78
1
1
1.5C6H6, 0.3CHCl3
1.5C6H6, 0.3CHCl3
-
-
2.71, 2.75
P
P
18b
18c
0.76 as above
a Unusually low and high packing densities are in italics; suggested correct values are in bold type. b H2TdMePP, tetra(3,5-dimethylphenyl)porphyrin;
H2TdBuPP, tetra(3,5-di-tert-butylphenyl)porphyrin; H2TpivPP, tetra(2-pivaloylphenyl)porphyrin; NiTMePP, nickel tetra(p-methylphenyl)porphyrinate; MOEP,
metal octaethylporphyrinate; P, parallel conformation; S, saddle conformation; k, packing coefficient. c Per one fullerene molecule. d Compound 5. e Compound
4. f Compound 1. g Compound 2. h Compound 3.
(C60)2O‚CoOEP‚0.4C6H6‚0.6CHCl313 most likely indicates a
misprint, whereas the tentative composition (C60)2O‚2CoOEP‚
0.4C6H6‚0.6CHCl3, with Z ) 2 instead of Z ) 4, gives the
normal value of k ) 0.74. Other outlying values of k in the
reported solvent-free complexes, viz. H2TdBuPP‚C60 (k )
0.68)14 and ZnTPP‚C70 (k ) 0.61),14 may be indicative of
the presence of some disordered solvent molecules, not
revealed in the original X-ray studies. This is very likely
the case for the latter compound, due to its isomorphism with
Structure Database (CSD) data for pure porphyrins and their
(fullerene-free) solvates showed saddle and planar conforma-
tions to be almost equally favorable. Raston and co-workers20
studied a series of related supramolecular fullerene complexes
with substituted tetraazo-macrocyclic derivatives of 3d
metals, in which a saddle conformation of the macrocyclic
moiety is forced by intramolecular steric repulsion.
The most common packing motifs in molecular complexes
with 1:2 and 1:1 porphyrin-to-fullerene ratios are zigzag
chains of alternating fullerene and donor molecules, the latter
being sandwiched between fullerenes (Figure 7a). A few
other arrangements, such as linear chains [D-C70-D-C70]n
in H2TdMePP‚C70‚4C7H8 and zigzag chains [D-C60-D-
C60]n with the symmetrically independent isolated C60
moieties in 2H2TdMePP‚3C60‚4C7H8, were observed.14 How-
ever, more interfullerene contacts, which give rise to chains
and frameworks of Cn, may also exist in fullerene-rich
compositions with D:Cn ratios of 1:2 and 2:3. A comple-
mentary motif in 1:1 complexes consists of zigzag chains
of fullerene moieties with “capping” porphyrins (Figure 7b),
15
CuTPP‚C70‚1.5C7H8‚0.5C2HCl3 (see below).
The porphyrin-fullerene ratio in the structurally studied
complexes of C60, C70, and M3N@C80 vary from 1:2 to 2:1.
In all complexes, little or no ground-state charge transfer
from donor to fullerene has been reported.13-18 The planar
conformation of the porphyrin macrocycle clearly predomi-
nates, although the porphyrin molecules attain a saddlelike
conformation, fitting the convex Cn moieties in solvent-free
H2TpivPP‚C60,14 2CuTPP‚C60,15 and CoTMPP‚C60 (4). The
predominance of planar macrocycle conformation probably
has its origin in packing forces, as a survey of Cambridge
3644 Inorganic Chemistry, Vol. 41, No. 14, 2002

Fullerene-Metal Tetraarylporphyrin Complex
Table 4. Series of Isomorphous Porphyrin/Fullerene Complexes
H2TPP‚2C60‚ CoTMPP‚2C60‚ H2TPP‚C60‚
CuTPP‚C70‚
1.5C7H8‚0.5C2HCl3 ZnTPP‚C70
2PyCoTPP‚C60‚ (PyZnTPP)2C60‚ (PyZnTPP)2C70‚
4C6H6
3C7H8
3C7H8
Cp2Fe‚C7H8
p2Fe‚C7H8
C7H8‚C2HCl3
system
a, Å
b, Å
monoclinic
13.7422(6)
20.765(1)
18.626(1)
90
91.814(4)
90
5312
monoclinic
13.984(1)
21.388(2)
18.178(2)
90
96.586(2)
90
5401
triclinic
14.2783(3)
16.7220(3)
17.0596(3)
69.115(1)
85.338(1)
78.164(1)
3725
triclinic
14.3756(6)
16.5497(8)
17.6590(9)
72.460(1)
86.278(1)
80.577(1)
3951
triclinic
14.4805(1)
16.5025(2)
17.7287(3)
72.623(1)
86.580(1)
80.574(1)
3988
monoclinic
30.5233(4)
19.5925(2)
19.2515(2)
90
92.067(1)
90
11505
C2/c
monoclinic
30.797(2)
19.532(2)
19.312(1)
90
91.861(2)
90
11611
C2/c
monoclinic
30.763(3)
19.825(2)
20.036(2)
90
92.250(2)
90
12210
C2/c
c, Å
R, deg
â, deg
γ, deg
V, Å3
space group
Z
P21/c
4
P21/c
4
P1h
2
P1h
2
P1h
2
4
4
4
Fcalc
k
1.481
0.74
1.538
0.75
1.437
0.76
1.445
0.71
1.260
0.61
1.433
0.73
1.434
0.72
1.400
0.69
2.6-3.0 Å are observed in a number of complexes listed in
Table 3. Although the distances from the fullerene carbon
atoms to the (empty) center of the neighboring macrocycle
in H2TPP and related metal-free porphyrins have similar
values, the shortened metal-fullerene contacts clearly cor-
relate to the orientational ordering of the C60 and C70
molecules (see isomorphous 1 and 2). The use of metal-
loporphyrins as disorder-hindering agents in mixed fullerene
crystals is therefore justified. However, this is not so clear
for molecular complexes of endohedral metallofullerenes, for
which the metal moiety may itself be disordered within the
carbon shell.18 In some cases even in the presence of the
shortened C‚‚‚M contacts the Cn moiety is disordered, as in
Ru(CO)OEP‚C60‚2C7H8.16 A family of quasi-isomorphous
crystals with similar molecular packing may include both
ordered metal-containing and disordered metal-free porphyrin
complexes of fullerenes (see Table 4). A specific M‚‚‚Cn
interaction therefore does not determine the supramolecular
arrangement of the complex as a whole, although it can bring
more ordering in favorable cases.
Figure 7. Schematic representation of different types of molecular
arrangement in fullerene/porphyrin complexes. The explanations are given
in the text.
which may be just another view on the same structure with
both Cn‚‚‚D and Cn‚‚‚Cn short contacts. For porphyrin-rich
complexes with a 2:1 composition, pairs of donor molecules
may exist in either [Cn-D-D-Cn] chains (Figure 7c) or
zigzag fullerene chains with double porphyrin caps (Figure
7d). The isolated supramolecular grouping D‚Cn‚D that exists
in the first packing type is observed also in our 2:1 complexes
1-3, in which a donor moiety with the axial Py ligand is
not planar.
Isomorphous porphyrin-fullerene complexes were re-
ported for 2MOEP‚C60‚CHCl3 (where M ) Co, Zn),13
MOEP‚C70‚C6H6‚CHCl3 (where M ) Co, Ni, Cu),13 and the
endohedral derivatives CoOEP‚(M3N@C80)‚solv (where M
) Sc, Er),18 as well as complexes 1 and 2 in this paper (Table
1). The first series may be extended with the complex
2ZnOEP‚C60‚2C6H6.16 The other three complexes of C60 with
MOEP (1:1), where M ) Cu and Pd,16 are also isomorphous.
However, a broader term of quasi-isomorphism can be used
in this class of compounds, in which crystals have close unit
cell parameters but more variable content. Three families of
quasi-isomorphous structures displayed in Table 4 include
the monoclinic complexes 1-3 (see Results), the pair of
monoclinic H2TPP‚2C60‚4C6H6 and CoTMPP‚2C60‚3C7H8,
and the triclinic crystals of H2TPP‚C60‚3C7H814, CuTPP‚
C70‚1.5C7H8‚0.5C2HCl3,15 and ZnTPP‚C70.14 Calculated den-
sity of 1.260 g‚cm-3 for ZnTPP‚C70 deviates drastically from
two other compounds of this family (1.437 and 1.445 g‚cm-3,
respectively), which provides an additional argument for the
presence of disordered solvent molecules in this crystal.
The shortened M‚‚‚C(fullerene) contacts in the range of
Conclusion
The study of the formation of fullerene complexes with
metal tetraarylporphyrins in the presence of ferrocene il-
lustrates synthetic possibilities of this method in preparing
both solvated multicomponent and solvent-free phases. In
the fullerene complexes with planar porphyrin molecules,
the vacancies can be occupied not only by solvent molecules
but also by other donor ones. The multicomponent complexes
D1‚D2‚C60‚Si (where D1 is a structure-forming molecule and
D2 is another donor molecule) obtained by this procedure
have potential for modification of their physical properties
(by changing D2), while retaining the crystal structure of the
compound (preserving the same D1). Using D2 molecules
with strong donor properties, one can change electronic
characteristics of the complexes.
The information on fullerene complexes with porphyrins
obtained so far shows great advantages of porphyrins as
compared to other organic π-donors in the design of
functional fullerene-based molecular solids. The complexes
have a great variety of packing motifs (from a three-
dimensional framework to isolated packing of fullerenes) and
conformational flexibility of porphyrin counterparts. Weak
secondary M‚‚‚C(fullerene) binding may prevent rotation of
fullerene molecules in favorable packing motifs. The pres-
Inorganic Chemistry, Vol. 41, No. 14, 2002 3645

Konarev et al.
ence of large vacancies or channels between planar porphyrin
molecules and spherical fullerenes allows incorporation of
other donor molecules into a complex.
99-03-32810 and 00-03-32577a), and the National Science
Foundation (CHE9981864).
Supporting Information Available: IR and UV-vis-NIR
spectroscopic data; five X-ray crystallographic files in CIF format.
This material is available free of charge via the Internet at
http://pubs.acs.org.
Acknowledgment. The work was supported by the
Linkage Grant of NATO Science Program, the Russian
Program “Fullerenes and Atomic Clusters”, Presidium of
Russian Academy of Sciences (Young Scientists’ Projects
program), Russian Foundation for Basic Research (Grants
IC011312L
3646 Inorganic Chemistry, Vol. 41, No. 14, 2002