Open AccessANALYTICAL POTENTIAL ENERGY FUNCTION FOR THE GROUND STATE (3Σ+u) OF UO2
Author(s) -
Hongyan Wang,
Tao Gao,
Yougen Yi,
Tan Mingliang,
Zhu Zheng-He,
Yongchun Fu,
Xiaolin Wang,
S. C. Ying
Publication year - 1999
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.48.2215
Subject(s) - ground state , potential energy , metastability , dissociation (chemistry) , physics , bond dissociation energy , atomic physics , statics , work (physics) , thermodynamics , chemistry , classical mechanics , quantum mechanics
An analytical potential energy function for the ground state 3Σ+u of UO2 has been derived using many-body expansion method. The present paper correctly determines the dissociation limits, based on group theory and atomic and molecular reactive statics (AMRS). Using the MP2 (The HF calculation followed by a second-order Moller-Plesset correlation) of Gaussian94W and the RECP (the relativistic effective core potential) for U and basis 6-311G* for O,the present work has optimized the equilibrium geometry for the ground state 3Σ+u of UO2, which is linear O—U—O,whose equilibrium nuclear distance and dissociation energy are 0.17789nm and 14.1036eV.And the metastable structure U—O—O is discovered for the first time,to our knowledge,which is 5.7731eV higher than the stable structure.Then,the potential energy function is successfully used for describing the equilibrium geometry of UO2 and UOO,which is accurate enough in the whole region for dynamical research.