Larrégaray, P.Cavina, A.Chergui, M.2011-04-122011-04-122011-04-12200510.1016/j.chemphys.2004.07.047https://infoscience.epfl.ch/handle/20.500.14299/66339WOS:000225814200003Non-polar solvation dynamics has been investigated using steady-state absorption and emission spectroscopy of the NO A(2)Sigma(+)(3ssigma) Rydberg state in fluid Ar over a wide range of densities spanning the supercritical regime. Equilibrium molecular dynamics simulations were implemented to derive a new isotropic NO A(3ssigma)-Ar pair potential which was further used to investigate the role of local density enhancements on the solvation process by non-equilibrium molecular dynamics simulations. These density inhomogeneities were found to have no influence on the solvation dynamics. Furthermore, the latter was shown to take place in a strongly non-linear regime, especially at low temperatures. This process results from the dramatic change of solute-solvent short range interaction associated with the large solute size change upon excitation to the Rydberg state.POLAR SOLVATION DYNAMICSVISCOELASTIC CONTINUUM MODELLENNARD-JONES FLUIDSSHORT-TIME DYNAMICSRARE-GAS MATRICESCRITICAL-POINTMOLECULAR THEORYDENSITY INHOMOGENEITIESVIBRATIONAL-RELAXATIONNONDIPOLAR SOLVENTStext::journal::journal article::research article