Weeks-Chandler-Andersen perturbation theory
The Weeks-Chandler-Anderson perturbation theory is based on the following decomposition of the intermolecular pair potential (in particular, the Lennard-Jones potential ):
The reference system pair potential is given by (Eq, 4 Ref. 1):
- Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle u_{\rm {repulsive}}(r)=\left\{{\begin{array}{ll}u_{\rm {LJ}}(r)+\epsilon &{\rm {if}}\;r<2^{1/6}\sigma \\0&{\rm {if}}\;r\geq 2^{1/6}\sigma \end{array}}\right.}
and the perturbation potential is given by (Eq, 5 Ref. 1):
- Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle u_{\rm {attractive}}(r)=\left\{{\begin{array}{ll}-\epsilon &{\rm {if}}\;r<2^{1/6}\sigma \\u_{\rm {LJ}}(r)&{\rm {if}}\;r\geq 2^{1/6}\sigma \end{array}}\right.}