原子与分子物理学报2017，Vol.34Issue(6)：1135-1141,7.DOI:10.3969/j.issn.1000-0364.2017.06.024
石墨烯力常数和弹性波波速随温度变化规律研究
Studies on the variations of force constants and the elastic wave velocities with temperature for grapheme
摘要
Abstract
This paper calculated, in Harrison bonded orbital method framework, the harmonic coefficients and non-harmonic coefficients of atomic vibrations by establishing the graphene elastic model with considering the anharmonic vibration of atoms and short-range interaction of atoms. Then the variation relationships among gra-phene force constants, temperature and deformation potential parametric, were obtained, and the variation rela-tionships among graphene elastic wave velocity, temperature and deformation potential parametric, were also ob-tained. Moreover, we discussed how the atomic anharmonic vibration impacts on graphene force constants and e-lastic wave velocity. The results were threefold. First, the three graphene force constants C11, C12、C44 the elastic wave velocity, unanimously, decrease nonlinearly with the temperature increasing, which the change order from largest to smallest of the constants is C12 , C11 , C44 , and the longitudinal wave velocity variation with temperature changes bigger than the shear wave. Second, the C11, C12、C44 with the change of deformation potential parame-ters have different characteristics:C11 enlargesw ith the increasing of η or γ, and C12 reduces with the increase ofη and increases with the increase ofγ, C44 increases with biggerηand nearly not change withγ. Third, the gra-phene force constants Cij and the elastic wave velocity vi are verified to be constants if we ignored the anharmonic term of atomic vibrations. Considering the anharmonic terms, all of these parameters Cij,vi, and |Cij-Cij0|、|vi-vi0|, the operator 'o' represents the approximate computing, decrease with increasing temperature, which means that the non-harmonic phenomenon is more obvious with higher temperature.关键词
石墨烯/非简谐效应/力常数/弹性波波速/形变势参量Key words
Graphene/Non-harmonic effect/Force constants/Elastic wave velocity分类
数理科学引用本文复制引用
高君华,申凤娟,干红平..石墨烯力常数和弹性波波速随温度变化规律研究[J].原子与分子物理学报,2017,34(6):1135-1141,7.基金项目
重庆市基础与前沿研究项目(cstc2015jcyjA40054) （cstc2015jcyjA40054）
重庆文理学院校级重点项目(Z2015DQ11) （Z2015DQ11）
重庆市教委科学技术研究项目(KJ1501105) （KJ1501105）
永川区科委自科基金(Ycstc,2015nc2001) （Ycstc,2015nc2001）
