科研之友
微信
新浪微博
Facebook
分享链接
摘要
Based on density functional theory the noncentrosymmetric superconductor Mo3Al2C in its well-established beta-Mn-type (P4(1)32) crystal structure is investigated. In particular, its thermodynamical and dynamical stabilities are studied by calculating lattice vibrations within the harmonic approximation. It is found that the fully stoichiometric compound is dynamically unstable. However, compounds with carbon vacancies (i.e., Mo3Al2C1-x) can be dynamically stabilized for vacancy concentrations x %26gt; 0.09. By means of a simple thermodynamical model we estimate x similar to 0.13-0.14 for Mo3Al2C1-x at the experimental preparation temperatures. The influence of the carbon vacancy concentration on the electronic structure is investigated.
- 出版日期2012-9-10
