文档介绍：Full-Potential LMTO
Total Energy and Force Calculations
J. M. Wills1, O. Eriksson2, M. Alouani3, and D. L. Price4
1 Los Alamos National Laboratory, Los Alamos, NM 87545, USA
2 Uppsala University, Uppsala, Sweden
3 IPCMS, 23rue du Loess, 67037Strasbourg, France
4 University of Memphis, Memphis, TN 38152, USA
Abstract. The essential features of a full potential electronic structure method using
Linear Muffin-Tin Orbitals (LMTOs) are presented. The electron density and potential
in the this method are represented with no inherent geometrical approximation. This
method allows the calculation of total energies and forces with arbitrary accuracy while
sacrificing much of the efficiency and physical content of approximate methods such as
the LMTO-ASA method.
1 Introduction
This paper describes a particular implementation of a full-potential electronic
structure method usingLinear Muffin-Tin Orbitals (LMTO’s) [2,10] as basis
functions. There have been several “FP-LMTO” implementations [3–7]. The one
described here has not been published in detail, although calculations performed
with this method have been reported for quite some time [3]. There are many
aspects to an electronic structure method. This paper is focussed on those aspects
which enable a full potential treatment. Relatively small details pertainingto
full-potential methods will be discussed while larger details having to do with,
for example, relativity will not be.
The emphasis of a variational full-potential method is somewhat different
from that of a method such as the LMTO-ASA method. The emphasis of the
former is on pleteness of the basis while in the latter it is in the phy-
sical content (and interpretability) of the basis. These concepts are, of course,
intimately related, but the emphasis is different.
The exposition here is for an infinite system periodic in three dimensions.
This method has been implemented for two-dimensional systems,[8] but that
will