Corresponding-states framework for classical and quantum fluids—Beyond Feynman–Hibbs.

This article focuses on developing a new three-parameter corresponding-states principle to accurately describe quantum fluids with strong nuclear quantum effects, such as liquid hydrogen and helium. By mapping quantum-corrected pair potentials—specifically those corrected via the Feynman–Hibbs (FH) approach—onto classical pair potentials with modified repulsive range parameters, the authors establish conformality between quantum and classical interactions through effective temperature- and mass-dependent parameters (σ_eff, ɛ_eff, and ν_eff). This framework enables the use of established classical fluid models (e.g., equations of state, classical density functional theory, and entropy scaling) to predict thermodynamic, structural, interfacial, and transport properties of quantum fluids with improved accuracy. Furthermore, by fitting these effective parameters directly to experimental data, the approach surpasses the limitations of traditional FH and Wigner–Kirkwood corrections, offering enhanced modeling capabilities for fluids exhibiting strong quantum behavior.