物理化学学报 >> 2000, Vol. 16 >> Issue (03): 238-242.doi: 10.3866/PKU.WHXB20000309

研究论文 上一篇    下一篇

ZnNe低激发态的量子化学研究

李西平, 涂学炎   

  1. 昆明理工大学基础部,昆明 650093|云南大学化学系,昆明 650091
  • 收稿日期:1999-07-05 修回日期:1999-11-15 发布日期:2000-03-15
  • 通讯作者: 李西平

Studies on the Quantum Chemistry for the Low-lying Excited States of ZnNe

Li Xi-Ping, Tu Xue-Yan   

  1. Department of Basic Science,Kunming University of Science and Technology,Kunming 650093|Department of Chemistry,Yunnan University,Kunming 650091
  • Received:1999-07-05 Revised:1999-11-15 Published:2000-03-15
  • Contact: Li Xi-Ping

摘要:

用相对论赝势CASSCF/CI方法,对ZnNe的基态 (X1∑ + )和低激发态 (A3∏、B3∑ +、C1∏和D1∑+ )进行了计算,得出了它们的电子结构,势能曲线及光谱常数. 计算结果表明, ZnNe的基态分子是范德华分子 ;它的几个低激发态分子中的主要作用力为范德华力,这些态的分子仍为范德华分子.

关键词: ZnNe, CASSCF/CI, 低激发态, 势能曲线, 光谱常数

Abstract:

The relativistic pseudopotential CASSCF/CI calculation has been performed for the ground state (X1Σ+) and a few low-lying excited states (A3Π,B3Σ+,C1Π and D1Σ+) of van der Waals molecule ZnNe. The electronic structure, the potential energy curves and the spectra constants of the states have been obtained. For the ground state (X1Σ+),the equilibrium distance(Re=0.43nm) obtained in this paper is in well agreement with the corresponding experimental value (0.43nm) and the dissociation energy (De=79cm-1) is good comparing with the experimental value (23.4cm-1). For the other states (A3Π, B3Σ+, C1Π and D1Σ+), the Re is 0.425, 0.55, 0.40 and 0.55nm, respectively and the De is 74.6,unstable,232.53 and 129.45cm-1 respectively. We think that these values are reasonable comparing with those of the similar molecule such as CdNe, although the corresponding experimental values are unavailable. The potential curves show that the wells of Πstates are deeper than those of the corresponding Σ states, and the bond lengths of Π states are shorter than those of the corresponding Σ states. From the electronic structure analysis, the bonds of ZnNe for the low-lying states can be described as the static charge attractive force which stems from atomic charge transfer produced by atomic orbital overlaps as well as van der Waals′force.

Key words: ZnNe, CASSCF/CI, Low-lying excited states, Potential energy curves, Spectra constants