Symmetry for lattice modes in C60 and alkali-metal-doped C60.
Symmetry for lattice modes in C60 and alkali-metal-doped C60.
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C60 和碱金属掺杂 C60 晶格模式的对称性。
DOI：
10.1103/physrevb.45.6923
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Eklund
中科院分区：
文献类型：
--
作者：
Dresselhaus;Eklund
我们提出了与解释 C 60 和碱金属掺杂 C 60 拉曼散射光谱最近实验观察相关的群论分析。群论分析利用了两个空间群，这两个空间群都将孤立的 C 60 分子的二十面体点群对称性降低到立方群 T h 。富勒烯的fcc排列的空间群是T h 6 ，对应于原始C 60 的低温固相。固体M 6 C 60 的bcc排列（其中M是碱金属）与空间群T h 5 一致，并且是完全掺杂的碱金属材料所考虑的对称性。实验拉曼光谱显示线分裂，这与富勒烯分子的对称性降低到 T h 对称性一致。然而，实验观察到的偏振选择规则表明对称性进一步降低，超出了立方对称性。
We present group-theoretical analysis relevant to the interpretation of recent experimental observations of Raman-scattering spectroscopy in C 60 and alkali-metal-doped C 60. The group-theoretical analysis makes use of two space groups, both of which reduce the icosahedral point-group symmetry of the isolated C 60 molecule to the cubic group T h. The space group for the fcc arrangement of fullerene is T h 6 and corresponds to the low-temperature solid phase of pristine C 60. The bcc arrangement for solid M 6 C 60, where M is an alkali metal, is consistent with the space group T h 5 and is the symmetry considered for the fully doped alkali-metal material. The experimental Raman spectra show line splittings which are consistent with a symmetry lowering to T h symmetry for the fullerene molecule. However, the polarization selection rules observed experimentally indicate a further lowering of the symmetry, beyond cubic symmetry.