Nonpolar solvation dynamics for a nonpolar solute in room temperature ionic liquid: a nonequilibrium molecular dynamics simulation study

摘要: Nonpolar solvation dynamics of a nonpolar diatomic solute in room temperature ionic liquid (RTIL) has been followed via nonequilibrium molecular (MD) simulation. Frank-Condon type excitation the solute, previously equilibrium RTIL solvent, modelled by abruptly changing Lennard-Jones (LJ) diameter atoms and thereby disrupting situation. The rearrangement solvent molecules, which seen to be mostly contributed solute’s first shell, around excited results overall spectral narrowing biphasic decay energy; dominant very rapid process having sub-100 fs relaxation time, slower one relaxing at timescale $$\sim $$ 5 ps. A mode-coupling theory based calculation is also used obtain function for model dissolved solvent. theoretical not good agreement with simulated response function; predicts short time component longtime faster than those relaxation. We have checked validity linear (LRT) looking energy correlation presence ground state (GS) (ES) solute. Apparent breakdown LRT present case elucidates probable disagreement between functions. SYNOPSIS nondipolar probe an imidazolium studied using classical simulation method. non-equilibrium functions compared experimentally measured (using 3PEPS) theoretically predicted mode coupling theory) function. study reveals that experimental timescales can originate from purely interaction molecules.