C60·2CHBr3 polycrystalline powder was prepared by the solution method. The vibrational modes of the sample were studied by Raman scattering and infrared adsorption techniques. The Raman spectra showed that the Ag...C60·2CHBr3 polycrystalline powder was prepared by the solution method. The vibrational modes of the sample were studied by Raman scattering and infrared adsorption techniques. The Raman spectra showed that the Ag modes were downshifted by 4-5 cm1, while the Hg(1) mode was unshifted. The analyses of the downshifts of the Ag modes revealed that a small amount of electrons were transferred from the hydrogen atoms to the C60 molecules. In the infrared spectra, the F1u modes of the pristine C60 were unshifted after the intercalation with CHBr3. However, the vibrational modes of CHBr3 changed remarkably. The C-Br stretching mode was downshifted by ～4 cm1. The adsorption of the C-H twisting mode was weakened obviously, and the adsorption of the C-H stretching mode was not observed. These results exhibited that there were nonnegligible interactions between CHBr3 and C60 molecules, and that the strongest interaction took place between the hydrogen atoms and the C60 molecules. The interaction should induce not only the changes of the vibrational modes reported here, but also those of the electronic states. So this work should offer important glues to the mechanism of the superconductivity at 117 K of the field-doped C60·2CHBr3.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.10074053)the Natural Science Foundation of Zhejiang Province(Grant No.100019).
文摘C60·2CHBr3 polycrystalline powder was prepared by the solution method. The vibrational modes of the sample were studied by Raman scattering and infrared adsorption techniques. The Raman spectra showed that the Ag modes were downshifted by 4-5 cm1, while the Hg(1) mode was unshifted. The analyses of the downshifts of the Ag modes revealed that a small amount of electrons were transferred from the hydrogen atoms to the C60 molecules. In the infrared spectra, the F1u modes of the pristine C60 were unshifted after the intercalation with CHBr3. However, the vibrational modes of CHBr3 changed remarkably. The C-Br stretching mode was downshifted by ～4 cm1. The adsorption of the C-H twisting mode was weakened obviously, and the adsorption of the C-H stretching mode was not observed. These results exhibited that there were nonnegligible interactions between CHBr3 and C60 molecules, and that the strongest interaction took place between the hydrogen atoms and the C60 molecules. The interaction should induce not only the changes of the vibrational modes reported here, but also those of the electronic states. So this work should offer important glues to the mechanism of the superconductivity at 117 K of the field-doped C60·2CHBr3.
