Nonlinear response theories and effective pair potentials
Abstract
We present a general method based on nonlinear response theory to obtain effective interactions between ions in an electron gas which can also be applied to other systems where an adiabatic separation of time-scales is possible. Nonlinear contributions to the interatomic potential are expressed in terms of physically meaningful quantities, giving insight in the physical properties of the system. The method is applied to various test cases and is found to improve the standard linear and quadratic response approaches. It also reduces the discrepancies previously observed between perturbation theory and density-functional theory results for the proton-proton pair potentials in metallic environments.
Cite
@article{arxiv.cond-mat/0703136,
title = {Nonlinear response theories and effective pair potentials},
author = {Simon Gravel and N. W. Ashcroft},
journal= {arXiv preprint arXiv:cond-mat/0703136},
year = {2007}
}
Comments
16 pages, 8 figures. v2: some added references, and a few minor modifications. To appear in Phys. Rev. B