闪锌矿结构的PtN:一种不稳定的过渡金属氮化物

基于密度泛函理论的第一性原理的赝势方法，采用局域密度近似和广义梯度近似，研究了闪 锌矿结构的PtN晶体的电子结构和力学稳定性.结果表明具有闪锌矿结构的PtN是一种力学不 稳定的金属氮化物，岩盐矿结构PtN的聚合能略大于闪锌矿结构PtN的聚合能，在适当压力条 件下可以发生从闪锌矿到岩盐矿的相变. 关键词： PtN 电子结构 力学稳定性 第一原理计算

PtN in zinc-blende structure: An unstable metallic transition-metal nitride compound

Using the first principle calculations based on density function theory with the generalized gradient approximation and local density approximation,we studied electronic structure and mechanical stability of the recently synthesized nitride compound PtN with cubic structure. The results show that the PtN with zinc-blende structure is unstable. We further find that the rock-salt structure has a bigger cohesive energy than the zinc-blende structure, it is possible that a phase transition from zinc-blende to rock-salt occurs under certain pressure.