Car-Parrinello molecular dynamics study of the blue-shifted F3CH...FCD3 system in liquid N2
Pawel Rodziewicz1, Konstanty S Rutkowski, Sonia M Melikova
1Faculty of Chemistry, University of Wroclaw, 14 F. Joliot-Curie, 50-383 Wroclaw, Poland. pawel.rodziewicz@gazeta.pl
Abstract:
Fluoroform, as confirmed by both experimental and theoretical studies, can participate in improper H-bond formation, which is characterized by a noticeable increase in the fundamental stretching frequency nu(C-H) (so-called blue frequency shift), an irregular change of its integral intensity, and a C-H bond contraction. A Car-Parrinello molecular dynamics simulation was performed for a complex formed by fluoroform (F3CH) and deuterated methyl fluoride (FCD3) in liquid nitrogen. Vibrational analysis based on the Fourier transform of the dipole moment autocorrelation function reproduces the blue shift of the fundamental stretching frequency nu(C-H) and the decrease in the integral intensity. The dynamic contraction of the C-H bond is also predicted. The stoichiometry of the solvated, blue-shifted complexes and their residence times are examined.
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