All-electron, real-space perturbation theory for homogeneous electric fields: theory, implementation, and application within DFT. (19th July 2018)

• Record Type: Journal Article
• Authors: Shang, Honghui; Raimbault, Nathaniel; Rinke, Patrick; Scheffler, Matthias; Rossi, Mariana; Carbogno, Christian
• Is Part Of: New journal of physics. Volume 20:Number 7(2018:Jul.)
• Publication Date: 2018-07-19
• Subjects: coupled perturbed self-consistent field method -- density-functional perturbation theory -- atom-centered basis functions -- homogeneous electric fields -- Raman spectra -- paracetamol; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/aace6d
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: Within density-functional theory, perturbation theory (PT) is the state-of-the-art formalism for assessing the response to homogeneous electric fields and the associated material properties, e.g., polarizabilities, dielectric constants, and Raman intensities. Here, we derive a real-space formulation of PT and present an implementation within the all-electron, numeric atom-centered orbitals electronic structure code FHI-aims that allows for massively parallel calculations. As demonstrated by extensive validation, we achieve a rapid computation of accurate response properties of molecules and solids. As an application showcase, we present harmonic and anharmonic Raman spectra, the latter obtained by combining hundreds of thousands of PT calculations with ab initio molecular dynamics. By using the PBE exchange-correlation functional with many-body van der Waals corrections, we obtain spectra in good agreement with experiment especially with respect to lineshapes for the isolated paracetamol molecule and two polymorphs of the paracetamol crystal.