A Full-Potential LMTO Method Based on Smooth Hankel Functions

Abstract

The paper presents a recently developed full-potential linear muffin-tin orbital (FP-LMTO) method which does not require empty spheres and can calculate the forces accurately. Similar to previous approacher;, this method uses numerical integration to calculate the matrix elements for the interstitial potential, which is the limiting step for any FP-LMTO approach. However, in order to reduce the numerical effort as far as possible, we use a newly introduced basis consisting of "augmented smooth Hankel functions" which play the role of the LMTO envelope functions. After presenting the basics of the approach, we report the results of numerical test for typical condensed-matter systems. The calculations show that good accuracy can be reached with an almost minimal basis set. These features of the method open the way to efficient molecular dynamics studies and simulated-annealing calculations to optimize structures while retaining the advantages of the LMTO method.