Raman scattering study of C120, a C60 dimer

Far-infrared vibrational properties of high-pressure high-temperatureC60polymers and theC60Long1, Musfeldt2, Kamarás3 et al. 2000Phys. Rev. B292330View full textAdd to dashboardCite

“…If such IR-active vibrations exist for the O and R polymers, they occur at frequencies below our range or are simply too weak to be detected. Interball vibrations have been observed in Raman spectra of the dimer, 14 photopolymer, 3,50 and HPHT polymers 12,34 in good agreement with calculated frequencies 28,30 and by inelastic neutron scattering in the O polymer. 51 Although IR-active interball modes are predicted near 22 and 35 cm Ϫ1 in the dimer, 30,31 we do not resolve them here.…”

“…26,28,[30][31][32] Such treatments usually have focused on the Raman spectra, for which calculated mode strengths are more reliable, 28,33 and which exhibit lowfrequency features characteristic of intermolecular vibrations. 3,14,15,34,35 In this paper, we report far-infrared ͑FIR͒ vibrational properties of the 2ϩ2 cycloaddition dimer, and the 1D orthorhombic and 2D rhombohedral HPHT C 60 polymers whose structures are shown in Fig. 1.…”

“…The observed polymerized C 60 structures include dimers 6,7 orthorhombic onedimensional ͑1D͒ chains, [8][9][10] tetragonal and rhombohedral two-dimensional ͑2D͒ lattices, 4,11 and some disordered 3D structures, 12 among others. 13 Methods of preparing the 2 ϩ2 cycloaddition dimer include mechanochemical reaction of C 60 with KCN or Li, 7,14 high-temperature phototransformation, 15 quasihydrostatic compression, 16 and pressurization of the template compound (ET) 2 C 60 . 17 Roomtemperature exposure of C 60 to visible or ultraviolet light creates a disordered array of small closed oligomers, referred to as the photopolymer.…”

“…18 In the linked fullerene structures, symmetry reduction of the ball yields spectra of increasing complexity, partly manifest in splitting of modes derived from the degenerate T 1u and H g vibrations of I h C 60 . 3,4,14,16,[22][23][24][25][26] Mode splittings of the rhombohedral HPHT polymer and linear chain RbC 60 were initially treated by group theory analysis, based on a weak perturbation assumption. 24 Later work found, however, that the weak perturbation picture is inadequate to explain certain widely split or shifted modes in the HPHT polymers and dimer.…”

Characterisation of Ni-C films obtained in PVD/CVD process

“…According to [21,22] the first band corresponds to H g (7) mode, whereas the second to A g (2) mode.…”