First-principles prediction of layered antiperovskite superconductors A2CNi4 (A = Al, Ga, and Sn)
First-principles prediction of layered antiperovskite superconductors A2CNi4 (A = Al, Ga, and Sn)
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DOI：
10.1063/1.4769882
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发表时间：
2012-11
期刊：
影响因子：
1.6
通讯作者：
D. Shao;W. Lu;S. Lin;P. Tong;H. Jian;X. Pan;Y. Sun
中科院分区：
文献类型：
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作者：
D. Shao;W. Lu;S. Lin;P. Tong;H. Jian;X. Pan;Y. Sun
采用基于密度泛函理论（DFT）的第一性原理计算方法，对不同A位元素的层状反钙钛矿型碳化镍A2 CNi 4进行了理论设计和研究.计算的一系列A位元素的形成能表明，Al_2CNi_4，Ga_2CNi_4和Sn_2CNi_4是稳定的，可以在常压下合成。计算并讨论了其弹性性质和电子能带结构。与超导MgCNi 3类似，这三种稳定的化合物显示出非磁性基态。在费米能级N（EF），占主导地位的Ni-3d电子的态密度，可以与MgCNi 3的N（EF）。电子和空穴带穿过费米能级，表明A2 CNi 4（A = Al，Ga和Sn）的多带性质。利用McMillan公式，我们近似地估计了电子-声子耦合常数λ和超导转变温度TC等超导参数。我们目前的研究结果表明，分层和…
We theoretically designed and investigated the layered antiperovskite nickel carbides A2CNi4 with different A-site elements by using the first-principles calculation based on density functional theory (DFT). The calculated formation energies for a series of A-site elements show that Al2CNi4, Ga2CNi4, and Sn2CNi4 are stable and can be synthesized at ambient pressure. The elastic properties and electronic band structures were calculated and discussed. Similar to the superconducting MgCNi3, the three stable compounds show the non-magnetic ground states. The density of states at Fermi level N(EF), dominated by Ni-3d electrons, can be comparable with the N(EF) of MgCNi3. The electron and hole bands cross the Fermi level, indicating the multiple-band nature for A2CNi4 (A = Al, Ga, and Sn). Using the McMillan's formula, we approximately estimated the superconducting parameters such as electron-phonon coupling constants λ and superconducting transition temperatures TC. Our present results show that the layered an...