TAILIEUCHUNG - Multiproperty empirical isotropic interatomic potentials for CH4–inert gas mixtures

An approximate empirical isotropic interatomic potentials for CH4–inert gas mixtures are developed by simultaneously fitting the Exponential-Spline-Morse-Spline-van der Waals (ESMSV) potential form to viscosity, thermal conductivity, thermal diffusion factors, diffusion coefficient, interaction second pressure virial coefficient and scattering cross-section data. Quantum mechanical lineshapes of collision-induced absorption (CIA) at different temperatures for CH4–He and at T = 87 K for CH4–Ar are computed using theoretical values for overlap, octopole and hexadecapole mechanisms and interaction potential as input. Also, the quantum mechanical lineshapes of collision-induced light scattering (CILS) for the mixtures CH4–Ar and CH4–Xe at room temperature are calculated. The spectra of scattering consist essentially of an intense, purely translational component which includes scattering due to free pairs and bound dimers, and the other is due to the induced rotational scattering. These spectra have been interpreted by means of pair-polarizability terms, which arise from a long-range dipole-induced-dipole (DID) with small dispersion corrections and a short-range interaction mechanism involving higher-order dipole–quadrupole A and dipole– octopole E multipole polarizabilities. Good agreement between computed and experimental lineshapes of both absorption and scattering is obtained when the models of potential, interaction-induced dipole and polarizability components are used. | Multiproperty empirical isotropic interatomic potentials for CH4–inert gas mixtures

• Hoá học
• Intermolecular potential
• CH4–inert gases
• CH4–inert gas mixtures
• Diffusion coefficient
• Scattering cross section data
• Journal of Chemistry
• Development of new cross intermolecular pair potential ab initio
• New cross intermolecular pair potential ab initio
• Cross second virial coefficients for dimer H2O CH4
• Cross second virial coefficients
• Ab initio calculation of the intermolecular potential
• Prediction of second virial coefficients for dimer H2 H2
• Second virial coefficients
• The basis set superposition error
• Interaction second virial coefficients
• Dimer co co from new ab
• Initio potential energy surface
• Intermolecular interaction potentials