有限温度におけるフォノンと結晶構造の第一原理計算:自己無撞着フォノンによるアプローチ
e-mail: sugino@issp.u-tokyo.ac.jp
First-principles structural optimization and phonon calculation based on density functional theory (DFT) are widely used and indispensable in modern materials science study. While these approaches are quite powerful for predicting ground state properties, predicting finite-temperature structures and phonons remains challenging because various elementary excitations, particularly phonons, and their temperature dependence need to be considered. In this seminar, we present a self-consistent phonon (SCP) theory [1] and its extension as an effective way to access finite-temperature phonons and structures. We discuss the accuracy and efficiency of the SCP approaches by showing our recent results on CsPbBr3 [2] and BaTiO3 [3].
[1] T. Tadano and S. Tsuneyuki, Phys. Rev. B 92, 054301 (2015).[2] T. Tadano and W. A. Saidi, arXiv:2103.00745.
[3] R. Masuki, T. Nomoto, R. Arita, and T. Tadano, arXiv:2205.08789.