Cr原子链的几何结构与电子性质研究

基于第一性原理方法研究Cr原子链可能形成的几何结构与电子性质.计算表明:Cr原子链可形成线性型、二聚化型、平面之字型和梯型等一维原子链.梯型结构的原子链结合能最大,稳定性最好,二聚化型结构次之,然后是大角度的之字型结构、小角度的之字型结构,线性结构的结合能最小.其中二聚化结构原子链的能带表现出间接带隙的特征,大角度之字型结构原子链为半金属性,小角度之字型结构原子链的能带则表现为较强的金属性.同时还讨论了这些结构的相对稳定性以及各链式结构的电子能带、电荷密度等性质.

Geometric and Electronic Structures of Chromium Atomic Chains

The structural stabilities and electronic structures of Cr atomic chains are studied by using first-principles plane wave pseudo-potential method based on the density functional theory.The present calculation results show that chromium can form planar chains in linear,zigzag,dimer,and ladder form one dimensional structures.The most stable geometry chain among the studied structures is the ladder-form chain.The dimer structure is found to be more stable than the zigzag one.Further more,the relative structural stability,the electronic energy bands,the density of states is discussed based on the ab initio calculations.