Analytical potential energy function for the ground state ((X)over-tilde(3)Sigma(+)(u)) of UO2

Citation
Hy. Wang et al., Analytical potential energy function for the ground state ((X)over-tilde(3)Sigma(+)(u)) of UO2, ACT PHY C E, 48(12), 1999, pp. 2215-2221
Citations number
11
Language
CHINESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
ACTA PHYSICA SINICA
ISSN journal
1000-3290 → ACNP
Volume
48
Issue
12
Year of publication
1999
Pages
2215 - 2221
Database
ISI
SICI code
1000-3290(199912)48:12<2215:APEFFT>2.0.ZU;2-Y
Abstract
An analytical potential energy function for the ground state (X) over tilde (3)Sigma(u)(+) of UO2 has been derived using many-body expansion method. Th e present paper correctly determines the dissociation limits, based on grou p theory and atomic and molecular reactive statics (AMRS). Using the MP2 (T he 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 ge ometry for the ground state (X) over tilde(3)Sigma(u)(+) of UO2 which is li near O-U-O, whose equilibrium nuclear distance and dissociation energy are 0.17789 nm and 14.1036 eV. And the metastable structure U-O-O is discovered for the first time, to our knowledge, which is 5.7731 eV higher than the s table structure. Then, the potential energy function is successfully used f or describing the equilibrium geometry of UO2 and UOO, which is accurate en ough in the whole region for dynamical research.