Speaker
Description
I will give a review on augmented plane wave (APW) methods for the calculation of the electronic structure in solids starting with the original concept developed by J. Slater [1] long time ago up to the APW+lo method introduced by Sjöstedt {\it et al.} [2]. This latter method combines the superior convergence behaviour of the original APW method with the convenience of LAPW [3]. I will then give an overview of the implementation of APW+lo into the WIEN2k code [4] and summarize the available features and discuss in particular the possibilities connected with calculations of phonons.
Selected results will be discussed in more detail. This will include phase transitions in RbCaF$_3$ [5] and PbTiO$_3$ [6] as well as a finite temperature (phonon) related explanation of a double peak occurring in the B-K XANES spectra of h-BN [7].
Refs
[1] J. Slater, Phys. Rev. {\bf 51}, 151 (1937).
[2] E. Sjöstedt, L. Nordström and D. Singh, Solid State Commun. {\bf 114}, 15 (2000).
[3] G. K. H. Madsen, P. Blaha, K. Schwarz, E. Sjöstedt and L. Nordström, Phys. Rev. B {\bf 64}, 195134 (2001).
[4] http://www.wien2k.at
[5] S. Ehsan, A. Tröster, F. Tran and P. Blaha, Phys Rev. Mat. {\bf 2}, 093610 (2018).
[6] A. Tröster, S. Ehsan, K. Belbase, P. Blaha, J. Kreisel and W. Schranz, Phys. Rev. B {\bf 95}, 064111 (2017).
[7] F. Karsai, M. Humer, E. Flage-Larsen, P. Blaha and G. Kresse, Phys. Rev. B {\bf 98}, 235205 (2018).
