文献类型：期刊文献

英文题名：BEEF-vdW plus U method applied to perovskites: thermodynamic, structural, electronic, and magnetic properties

作者：Li, Yang[1];Zheng, Ya-Shan[1];Zhu, Yi-An[1];Sui, Zhi-Jun[1];Zhou, Xing-Gui[1];Chen, De[2];Yuan, Wei-Kang[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, UNILAB, Shanghai 200237, Peoples R China;[2]Norwegian Univ Sci & Technol, Dept Chem Engn, N-7491 Trondheim, Norway

年份：2019

卷号：31

期号：14

外文期刊名：JOURNAL OF PHYSICS-CONDENSED MATTER

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000458635100001)】；

基金：This work is supported by the Natural Science Foundation of China (21473053, 91645122, and U1663221), the National Key Research and Development Program of China (2018YFB0604700), and the Fundamental Research Funds for the Central Universities (222201718003).

语种：英文

外文关键词：GGA plus U; perovskite; formation energy; band gap; magnetic moment

摘要：The recently developed BEEF-vdW exchange-correlation method provides a reasonably reliable description of both long-range van der Waals interactions and short-range covalent bonding between molecules and surfaces. However, this method still suffers from the excessive electron delocalization that is connected with the self-interaction error and, consequently, the calculated chemical and physical properties such as formation energy and band gap deviate markedly from the experimental values, especially when strongly correlated systems are under investigation. In this contribution, BEEF-vdW+U calculations have been performed to study the thermodynamic, structural, electronic, and magnetic properties of La-based perovskites. An effective interaction parameter U-eff and an energy adjustment Delta E-M are determined simultaneously by a mixing GGA and GGA+U method, where the enthalpy or Gibbs free energy of formation of oxides containing a transition metal in different oxidation states are fitted to available experimental data. The Delta E-M is found to have its origin in the fact that the GGA+U method gives rise to the offsets in the total energy that include not only the desired physical correction but also an arbitrary contribution. Calculated results indicate that the BEEF-vdW method provides a more accurate description of the bonding in the O-2 molecule than the PBE method and has generally smaller U-eff values for the 3d-block transition metals, thereby giving rise to band gaps and magnetic moments that are in better agreement with the experimentally measured values.