{ "id": "2201.04009", "version": "v2", "published": "2022-01-07T15:58:50.000Z", "updated": "2022-06-11T19:02:30.000Z", "title": "Mathematical Analysis of the van der Waals Equation", "authors": [ "Emil M. Prodanov" ], "comment": "11 pages, 5 figures", "journal": "Physica B: Condensed Matter 640, 414077 (2022)", "doi": "10.1016/j.physb.2022.414077", "categories": [ "cond-mat.stat-mech" ], "abstract": "The parametric cubic van der Waals polynomial $\\,\\, p V^3 - (R T + b p) V^2 + a V - a b \\,\\,$ is analysed mathematically and some new generic features (theoretically, for any substance) are revealed: the temperature range for applicability of the van der Waals equation, $T > a/(4Rb)$, and the isolation intervals, at any given temperature between $a/(4Rb)$ and the critical temperature $8a/(27Rb)$, of the three volumes on the isobar-isotherm: $\\,\\, 3b/2 < V_A \\le 3b$, $ \\,\\, 2b < V_B < 4b/(3 - \\sqrt{5})$, and $\\,\\, 3b < V_C < b + RT/p$. The unstable states of the van der Waals model have also been generically localized: they lie in an interval within the isolation interval of $V_B$. In the case of unique intersection point of an isotherm with an isobar, the isolation interval of this unique volume is also determined. A discussion on finding the volumes $V_{A, B, C}$, on the premise of Maxwell's hypothesis, is also presented.", "revisions": [ { "version": "v2", "updated": "2022-06-11T19:02:30.000Z" } ], "analyses": { "keywords": [ "van der waals equation", "mathematical analysis", "isolation interval", "cubic van der waals polynomial", "parametric cubic van der waals" ], "tags": [ "journal article" ], "publication": { "publisher": "Elsevier" }, "note": { "typesetting": "TeX", "pages": 11, "language": "en", "license": "arXiv", "status": "editable" } } }