γFe-N合金中N-Fe的交互作用

Interaction Between Nitrogen and Iron in γ Fe-N Alloy

利用基于第一原理的离散变分法 (DVM)计算了γ Fe- N合金的电子结构 ,分析了 N- Fe间的交互作用 .计算得到间隙 N分别与周围不同近邻的 4种 Fe原子的平均键级 ,通过比较它们随点阵畸变的变化后发现 ,N- Fe(1 )的键级大于另外 3种键级 ,说明γ Fe- N合金中 N与置换原子的交互作用主要集中在 N与最近邻原子之间 .并结合态密度、价轨的电子占据数和电子密度对其进行了综合分析 .

The interaction between nitrogen and iron in fcc Fe-N alloy was investigated by employing first principle's electronic structure calculations based on the discrete variational method (DVM). The average bond order (BO) of nitrogen and various neighboring substitutial atoms varies with the lattice distortion. Their values are compared and the results show that the BO of nitrogen and the nearest iron is the strongest, so it can be considered as the most important interaction of N and Fe in alloy. The density of states, the electron occupation of valence orbits and difference electron density are combined to analyze the viewpoint mentioned above.