摘要
First-principles calculations were carried out to investigate the structural stabilities and electronic properties of RhZr.The plane wave based pseudopotential method was used,in which both the local density approximation(LDA) and the generalized gradient approximation(GGA) implanted in the CASTEP code were employed.The internal positions of atoms in the unit cell were optimized and the ground state properties such as lattice parameter,density of state,cohesive energies and enthalpies of formation of ortho-RhZr and cubic-RhZr were calculated.The calculation results indicate that ortho-RhZr can form more easily than cubic-RhZr and the ortho-RhZr is more stable than cubic-RhZr.The density of states(DOS) reveals that the strong bonding in the Rh-Zr and Rh-Rh or Zr-Zr interaction chains accounts for the structural stability of ortho-RhZr and the hybridization between Rh-4d states and Zr-4d states is strong.
用第一性原理计算研究RhZr两种晶体结构的结构稳定性和电子结构性质。采用基于第一性原理的平面波赝势法,分别用局域密度近似和广义梯度近似法,对晶体原子的结构进行优化,并分别对正交晶系RhZr和立方晶系RhZr的基态性质,如晶格参数、能态密度、形成能以及形成焓等进行计算。计算结果表明:正交晶系RhZr比立方晶系RhZr更容易生成,而且生成的正交晶系RhZr比立方晶系RhZr更稳定。能态密度计算结果表明:立方晶系RhZr比正交晶系RhZr稳定,是因为在立方晶系RhZr中不仅存在Rh?Zr还存在Rh?Rh或者Zr?Zr之间的相互作用键。由态密度分析还可看出,在费米面附近Rh的4d轨道与Zr的4d轨道存在较强的轨道杂化。
基金
Project(u0837601)supported by the National Natural Science Foundation of China