DENSITY DEPENDENCE OF EXCESS ELECTRONIC GROUND-STATE ENERGIES IN SIMPLE ATOMIC FLUIDS

被引:67
作者
SPACE, B
COKER, DF
LIU, ZH
BERNE, BJ
MARTYNA, G
机构
[1] COLUMBIA UNIV, DEPT CHEM, NEW YORK, NY 10027 USA
[2] UNIV PENN, DEPT CHEM, PHILADELPHIA, PA 19104 USA
关键词
D O I
10.1063/1.463138
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The ground-state energies of an excess electron E0 as a function of solvent density are computed using model electron-atom pseudopotentials in fluid helium, argon, and xenon. E0 is a lower bound to the experimentally measurable threshold to photoconductivity, V0. The nonuniqueness of the pseudopotential description of electron-molecule interactions is demonstrated. We find that when many-body polarization effects are included, our calculated E0 results are in close agreement with experimental V0 values indicating that the conduction-band energy lies close to the ground-state energy across a broad range of densities in these polarizable fluids. If the many-body nature of the polarization interaction is ignored the ground-state energies deviate significantly from the V0 results highlighting the importance of accurate treatment of many-body polarization interactions. It is shown that a mean-field theory of polarization gives substantial agreement with full many-body calculations. This allows us to introduce a mean-field, density-dependent pair potential which greatly simplifies such many-body calculations. In the more polarizable systems, it is found that the spatial extent of the ground-state wave function as a function of solvent density is correlated with the density dependence of both V0 and the electron mobility, and it becomes uniformly spread throughout our simulation cell as the electron mobility goes through its maximum value at intermediate solvent densities.
引用
收藏
页码:2002 / 2021
页数:20
相关论文
共 54 条