Vibrational energy relaxation in classical fluids. II. High-frequency spectra in liquids

Abstract

Articles you may be interested inOn the calculation of vibrational energy relaxation rate constants from centroid molecular dynamics simulations J. Chem. Phys. 119, 9030 (2003); 10.1063/1.1613636 High-frequency vibrational energy relaxation in liquids: The foundations of instantaneous-pair theory and some generalizationsA procedure is outlined to determine high-frequency spectra of classical liquids interacting via Lennard-Jones and similar potentials and applied to the problem of vibrational energy relaxation. The theory is based on analytical expressions derived for spherical particles in gases ͓Paper I, D. Schwarzer and M. Teubner, J. Chem. Phys. 116, 5680 ͑2002͔͒ and is extended to the dense liquid phase by considering binary collisions in the potential of mean force. The calculated spectra are in good agreement with those derived from classical trajectory and molecular dynamics simulations.

Molecular dynamics modeling of cooling of vibrationally highly excited carbon dioxide produced in the photodissociation of organic peroxides in solution

“…The plot illustrates that the presence of solvent vibrations dramatically increases CET rate. For xenon the expected slightly stretched exponential decay 45 of the frequency dependence of the rate constants is observed leading to a practically exclusive contribution of the CO 2 lowest frequency vibration (the bend mode) to the energy transfer. In contrast, the spectra of CCl 4 and CH 2 Cl 2 are structured by pronounced resonant features arising from vibrational modes of the solvents.…”

Intramolecular vibrational energy redistribution and intermolecular energy transfer of benzene in supercritical CO2: measurements from the gas phase up to liquid densities

“…The force components contributing to nðxÞ are known to be generated at the repulsive part of the solute-solvent interaction potential. Therefore, k VET ðqÞ depends on the local density at shorter distances than the position of g max [34]. However, the local densities at both positions are strongly correlated and show similar density dependencies [35].…”

ND-stretching vibrational energy relaxation of NH2D in liquid-to-supercritical ammonia studied by femtosecond midinfrared spectroscopy

“…37 The MD simulations were performed in a cubic simulation box with periodic boundary conditions containing 500 particles as described previously. 54,55 Using the leapfrog algorithm, the equations of motions were integrated with a time step of ⌬t = 4 fs. After equilibration, the breathing sphere force F i ͑t͒ acting on each particle i was recorded for 2 19 time steps.…”

“…The individual spectra are characterized by a stretched exponential shape. 54,55 For a given temperature, the relaxation rate grows with increasing density regardless of the oscillator frequency. This increase is essentially caused by the density dependence of the collision frequency.…”