摘要
采用基于密度泛函理论广义梯度近似下的平面波赝势方法研究了刚玉(α-Al2O3)的阻氢微观机制,对氢原子在α-Al2O3中的占据结构进行了计算,发现氢原子占据空隙位置时能量最低,寻找其过渡态得到活化能为1.59eV,利用动力学计算得到了氢原子在α-Al2O3中的扩散系数表达式为D(T)=(3.37×10-7)exp(-1.59/kT).结果表明,氢原子占据在α-Al2O3八面体空隙处的结构最稳定;低温时扩散难以发生;高温时扩散沿着空隙方向.
The diffusion of hydrogen in corundum was simulated using pseudopotential plane wave method which was based on the density functional theory（DFr） with the generalized gradient approximation（GGA） to the exchange-correlation energy, The hydrogen permeation resistance and micromechanism were studied by searching the transition state and diffusion route, and gained diffusion coefficient of hydrogen by applying dynamic calculations. The activation energy was 1.59 eV and the diffusion coefficient of hydrogen was D（T）=（3.37×10^-7）exp（-1.59/kT）. Analyzing the calculation results, it showed that the structure in which H atom occupied empty interstitial of α-Al2O3 was more stable. H diffusion was impossible at low temperature and occured along the empty interstitials at high temperature.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2007年第12期1912-1916,共5页
Acta Physico-Chimica Sinica
