Vibrational spectra of fused salts and dynamic criterion of complex formation in ionic liquids

Abstract

Possible relations between several characteristic times, viz. the vibrational dephasing time τ V , the vibrational frequency modulation time τ ω , the time between collisions in a liquid τ BC, the collision duration time τ d , and the half-period of vibration T/2 are considered. It is found that for instantaneous collision complexes the following relations hold: τ ω ≈ T/2 or τ V ≈ T/2. For short-lived complexes τ ω ≤ τ d or τ V ≤ τ d , and 0.5≤ τ ω / T≤2 or0.5≤ τ V / T≤2, whereas for long-lived species τ ω ≤ τ d or τ V ≤ τ d , and τ ω ,/ T≥2 or τ V / T≥2.