On the reliability of linear band structure methods

TL;DR

This paper evaluates the accuracy of various band structure computational methods in predicting the Fermi surface of ErGa3, revealing discrepancies between modern full potential codes and experimental data, with implications for computational choices.

Contribution

It compares the performance of different band structure algorithms, highlighting unexpected inconsistencies with experimental results and suggesting the impact of linearization energy choices.

Findings

FP codes do not match experimental data as well as LMTO-ASA.

LMTO-ASA results align perfectly with experimental electron-positron momentum densities.

Discrepancies may be due to the choice of linearization energy in FP methods.

Abstract

We discuss an efficiency of various band structure algorithms in determining the Fermi surface (FS) of the paramagnetic ErGa3. The linear muffin-tin orbital (LMTO) in the atomic sphere approximation (ASA) method and three full potential (FP) codes: FP-LMTO, FP linear augmented plane wave (FLAPW), and FP local orbitals (FPLO) methods are employed. Results are compared with electron-positron (e-p) momentum densities reconstructed from two dimensional angular correlation of annihilation radiation (2D ACAR). Unexpectedly, none of used modern FP codes is able to give satisfying description of the experimental data that are in perfect agreement with LMTO-ASA results. We suspect that it can be connected with a different choice of the linearization energy.