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The Muffin-tin potential

A potential that overcomes the objectionos with the cellular method is the Muffiin-tin potential, whcih is taken to represent an isolated ion within an spehere of radius $r_0$ around each lattice point, and taken to be constant elsewhere. The muffin-tin potential mitigates both problems, being flat in the intestitial region, and leading to matching conditions on a spherical, rather than a polyhedral surface.

Formally, the muffin-tin potential can be defined by:

\begin{displaymath}
U_{m-t}({\bf r}) = \left\{
\begin{array}{cc}
V(\vert{\bf r} ...
...,  \vert{\bf r} - {\bf R}\vert\geq r_0 \\
\end{array}\right.
\end{displaymath} (241)

where $r_0$ is less than half the distance between neighboring sites.



Adrian E. Feiguin 2009-11-04