Open AccessMolecular dynamics simulation of surface energy of low miller index surfaces in UO2
Author(s) -
Hongxing Xiao,
Chongsheng Long
Publication year - 2013
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.62.103104
Subject(s) - materials science , surface energy , relaxation (psychology) , surface (topology) , molecular dynamics , ion , surface layer , range (aeronautics) , bar (unit) , chemical physics , crystallography , layer (electronics) , nanotechnology , chemistry , computational chemistry , physics , composite material , psychology , social psychology , geometry , mathematics , organic chemistry , meteorology
Molecular dynamics simulation based on the rigid-ion potential is carried out to investigate the surface energies of low miller index crystallographic faces such as (100), (110) and (111) in UO2 in a temperature range of 300 K-1500 K. The results indicate that the surface energies of the three low miller index crystallographic faces decline gradually with temperature rising, and the variation of the surface energy with temperature is confirmed to be consistent with the experimental data. The (111) crystallographic face which is the closest surface has the lowest surface energy; the (100) crystallographic face has the biggest surface energy; the (100) crystallographic face has a surface energy in between them. The surface atoms have compressed towards the vertical line of surface with respect to the inside atoms layer obviously. The symmetry of surface atoms declines. Surface phenomena such as relaxation and reconstruction occur on the surface atoms and the relaxation effect extends to the five layers. The results presented in the study are useful for understanding the behaviors of fission gas bubbles growing up and cracking up due to the swelling in fuels under the irradiation.