Optimized pseudopotentials for electronic structure calculations
CIMRMAN, R. ., VACKÁŘ, K. ., NOVÁK, M. . Optimized pseudopotentials for electronic structure calculations. Olomouc, 2019.
|Anglický název:||Optimized pseudopotentials for electronic structure calculations|
|Autoři:||Ing. Robert Cimrman Ph.D. , Kiří Vackář , Matyáš Novák|
|Abstrakt EN:||The electronic structure calculations represent a rigorous tool for predicting and understanding the properties of materials from first principles. Our research in this field is motivated by the interest in a detailed modelling of cracks in iron, where we wish to compute potentials for molecular dynamics simulations around a crack tip that would be as precise as possible. Within the context of the density functional theory, a pseudopotential approach is often used to reduce numerical difficulties by hiding the core singularity as well as non-valence electrons. However, designing an accurate and efficient pseudopotential is a non-trivial task as there are many, often contradictory, criteria on the pseudopotential ``optimality'', such as smoothness, softness (no strongly oscillating pseudo-wave-functions), transferability (validity in different neighboring atom configurations, reproduction of scattering properties in a wide range of energies), computational efficiency, etc. In the contribution we describe our approach and its new implementation for generating and optimizing the so called environment-reflecting all-electron pseudopotentials, that have many desirable properties, for example the applicability to an atom site-specific configuration. Several strategies for both the pseudopotential optimization and the related nonlinear constraints resolution will be presented using numerical examples computed with our code.|