N. G. Spitsyna

EELS, XPS and IR study of C60·2S8 compound

Abstract Results from electron energy loss, X-ray photoelectron, and infrared spectroscopies are ptesented for the C 60 ·2S 8 compound. As one goes from C 60 to C 60 ·2S 8 , binding energy decreases by 0.5 eV, and ( σ + π ) plasmon energy decreases by 1.2 eV. Arguments for charge redistribution are performed.

A complex of buckminsterfullerene with sulfur, C602S8: synthesis and crystal structure

The C60·2S8 complex was prepared by reaction of buckminsterfullerene C60 with sulfur in trichloroethylene and its single-crystal X-ray structure was studied at room temperature. Crystals of this compound are monoclinic, space groupC 2/c, a=20.90(1),b=21.10(1),c=10.537(9) Å, β=111.29(7)°,Z=4,dcalc=1.89 g·cm−3. The crystal structure of the C60·2S8 complex consists of packed fullerene molecules that form hexagonal channels along thec axis with eight-membered crown-shaped S8 cyclic molecules inside the channels. The distances between the centers of neighboring fullerene molecules are 10.036(7), 10.636(7), and 10.537(9) Å. Each C60 molecule is linked to eight S8 molecules with ten shortened intermolecular contacts C...S 3.41(1)–3.52(2) Å. The average values of the C=C and C-C bond lengths are 1.32(3) and 1.47(3) Å, which attest to a significant degree of localization of electron density in the c60 molecule.

Crystal and molecular structures of new fullerides, (Ph4P)2C60Hal (Hal=Br or I) and (Ph4As)2C60Cl

New air-stable fullerides, (Ph4P)2C60Hal (Hal=Br or I) and (Ph4As)2C60Cl, were synthesized, and their crystal structure were determined. A comparative crystal-chemical analysis of the fullerides under study demonstrated that they are isostructural, described by the general formula (Ph4X)2C60Hal (X=P or As, and Hal=Cl, Br, or I), and crystallize in the triclinic system. The C60− and Hal− anions occupy special centrosymmetric positions. The (Ph4P)+ and (Ph4As)+ cations occupy general positions. The principal parameters of the molecular structures are reported.

Crystal structure of a new molecular complex of fullerene with tetramethyltetraselenafulvalene: C60·TMTSF·2CS2

A new molecular complex of fullerene with tetramethyltetraselenafulvalene (TMTSF), C60·TMTSF·2CS2, (1) was synthesized. The structure and composition of the complex were established by X-ray diffraction analysis. The crystals of C60·C10H12Se4·2CS2 are monoclinic:a=15.407(2),b=12.934(2),c=12.026(2) Å β=108.39(3)°,V=2274.1(6) Å3, space groupCm, Z=2,dcalc=1.929 g cm−3,R=0.047. The crystal structure of 1 consists of layers. Layers formed by fullerene and CS2 molecules alternate with layers of TMTSF molecules. Peculiarities of the crystal structure of 1 are the nonplanar conformation of TMTSF molecules and the absence of shortened C…C contacts between adjacent fullerenes molecules. The energy of intermolecular TMTSF…C60 interactions in the crystal was estimated.

Crystal and Molecular Structure of a New Complex of [60]Fullerene, 2(C60)·2(TMTSF)·(C6H6)

Abstract A new molecular complex of [60]fullerene with composition 2(C60)·2(TMTSF)·(C6H6) was synthesized. The structure and composition of the complex were found by an x-ray study. Crystal data: 2(C60)2(C10H12Se4)(C6H6), M = 2415.4, monoclinic, a = 19.388(4), b = 13.410(2), c = 32.467(6) A, β = 92.71(2)°, V = 8432(3) [Adot]3, space group P21/n, Z = 4, dcalc = 1.903 g/cm3, R = 0.0606. The crystal structure was shown to be layered with the alternating layers of three types. Two of them have the same composition (C60, TMTSF) but different interorientation of molecules in a layer and different number of shortened contacts C…C and C…Se. The third layer consists of benzene molecules. The energy of intermolecular interactions C60…. TMTSF was estimated by ab initio calculations. The TMTSF molecule has a “boat” conformation.

Electron spectroscopy study of (ET)2C60 compound

Abstract Results of X-ray photoelectron spectroscopy (XPS) and electron energy loss spectroscopy (EELS) studies are presented for the (ET) 2 C 60 compound. It was established that XPS data correspond to small value of charge transfer in the complex. Loss function of (ET) 2 C 60 was extracted from EEL spectra. Energy of main ( σ + π ) plasmon h ω=23.8 eV was determined.

STUDY OF C60.2S8 BY THE METHODS OF INDUCED ELECTRON EMISSION

It was shown by the methods of induced electron emission that a transfer of the electron density from C60 molecules to the eight-membered ring of sulfur is characteristic of C60·2S8. The value of the (σ+π)-plasmon energy for C60·2S8 is approximately 1 eV less than that for pure C60. In a high vacuum, the C60·28 surface is depleted in sulfur.