Vibrational spectroscopic study of the ionic association and ion-pair structures in solutions of silver(I), copper(I) and thallium(I) thiocyanates in N,N-dimethylthioformamide

Effect of ion–molecule interaction on fermi-resonance in acetonitrile studied by ultrafast vibrational spectroscopy

“…Accordingly, such ion-molecule interactions have been extensively studied by FTIR experiments and theoretical methods for a few decades [1][2][3][4][5][6][7]. However, the effect of ions on vibrational dynamics of a given molecule has begun to be investigated recently with an advent of time-resolved vibrational spectroscopic techniques such as ultrafast infrared-Raman, infrared pump-probe (IR PP), and two-dimensional IR (2DIR) experiments [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]. A vibrationally excited molecule undergoes different relaxation processes on various timescales including vibrational energy transfer to anharmonically coupled vibrational modes [23,24], vibrational energy dissipation into the solvent [25], and resonance energy transfer to nearby vibrational modes with similar vibrational energies [26][27][28][29][30].…”

“…(9) is used to analyze the oscillatory components. The oscillatory components of IR PP signals for both m 2 and m 3+4 modes of CH 3 CN are well fit by the same frequencies of m 0 = 1.22 ps À1 (=40.7 cm À1 ) which is corresponding to the frequency difference between m 2 and m 3+4 modes.…”