2002/05/07 by A. A. Louis, A A Louis · 3 citations
Chemistry · Earth and Planetary Sciences · Physics and Astronomy · #Advanced Physical and Chemical Molecular Interactions #Electrostatics and Colloid Interactions #High-pressure geophysics and materials #cond-mat.mtrl-sci #cond-mat.soft
paper · pdf · doi:10.1088/0953-8984/14/40/311
published as . Phys.: Condens. Matter 14 9187-9206 (2002) · 22 pages, uses iopart.cls and iopart10.clo; submitted to Journal of Physics Condensed Matter, special issue in honour of professor Jean-Pierre Hansen
arxiv created 2002/05/07 · openalex publication_date 2002/09/26 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
Density (or state) dependent pair potentials arise naturally from coarse-graining procedures in many areas of condensed matter science. However, correctly using them to calculate physical properties of interest is subtle and cannot be uncoupled from the route by which they were derived. Furthermore, there is usually no unique way to coarse-grain to an effective pair potential. Even for simple systems like liquid argon, the pair potential that correctly reproduces the pair structure will not generate the right virial pressure. Ignoring these issues in naive applications of density dependent pair potentials can lead to an apparent dependence of thermodynamic properties on the ensemble within which they are calculated, as well as other inconsistencies. These concepts are illustrated by several pedagogical examples, including effective pair potentials for systems with many-body interactions, and the mapping of charged (Debye–Hückel) and uncharged (Asakura–Oosawa) two-component systems onto effective one-component ones. The differences between the problems of transferability and representability for effective potentials are also discussed.