Environmental fluctuations and rotational processes in liquids

Abstract

This work concerns diffusive and jump mechanisms for molecular rotation in liquids. Both τ₁ and τ₂, autocorrelation times characterizing the decay of the first- and second-order Legendre functions, are treated. The magnitudes of τ₁ and τ₂ are strongly dependent upon jump size. The (τ₂/τ₁) ratio is (1/3) for very small-angle jumps, and becomes infinite for jumps approaching 180°. The influence of environmental fluctuations on relaxation is considered: computer simulation techniques were used for this purpose. Slow environmental fluctuations tend to produce apparent correlation time distributions, while fast fluctuations generate relaxation characterized by exponential correlation functions.