Effects of Off-Diagonal Electron-Electron Interactions on Exciton Energies in C60
RAO Xue-song, ZHAO Hua, FU Rou-li, SUN Xin, K. NASU1
T. D. Lee Laboratory and Department of Physics, Fudan University, Shanghai 200433
and National Laboratory of Infrared Physics, Chinese Academy of Sciences, Shanghai, 200083
1National Laboratory for High Energy Physics, Tsukuba, Ibaraki 305, Japan
Effects of Off-Diagonal Electron-Electron Interactions on Exciton Energies in C60
RAO Xue-song;ZHAO Hua;FU Rou-li;SUN Xin;K. NASU1
T. D. Lee Laboratory and Department of Physics, Fudan University, Shanghai 200433
and National Laboratory of Infrared Physics, Chinese Academy of Sciences, Shanghai, 200083
1National Laboratory for High Energy Physics, Tsukuba, Ibaraki 305, Japan
Abstract： Since the neighboring π orbits in C60 are well overlapped, the off-diagonal part of electron interaction plays an important role. In this paper, the effects of the off-diagonal electron interactions on the exciton energies in C60 are studied by using the single configuration interaction approach. It is found that the binding energies of the low-lying singlet and triplet excitons depend sensitively upon the off-diagonal interactions which compete against the diagonal interactions and suppress the binding of the excitons. The implication of these features is discussed.
1996, Vol. 13 
