# Force calculation and atomic-structure optimization for the full-potential linearized augmented plane-wave code WIEN

## Description

Abstract Following the approach of Yu, Singh, and Krakauer [Phys. Rev. B 43 (1991) 641], we extended the linearized augmented plane wave code WIEN of Blaha, Schwarz, and coworkers by the evaluation of forces. In this paper we describe the approach, demonstrate the high accuracy of the force calculation, and use them for an efficient geometry optimization of poly-atomic systems. Title of program: fhi95force Catalogue Id: ADCW_v1_0 Nature of problem For ab-initio studies of the electronic and magnetic properties of poly- atomic systems, such as molecules, crystals and surfaces, it is of paramount importance to determine stable and metastable atomic geometries. This task of structure optimization is greatly accelerated and, in fact, often only feasible if the forces acting on the atoms are known. The computer code described in this article enables such calculations. Versions of this program held in the CPC repository in Mendeley Data ADCW_v1_0; fhi95force; 10.1016/0010-4655(95)00139-5 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019)