화학공학소재연구정보센터
Journal of Physical Chemistry B, Vol.117, No.16, 4354-4364, 2013
Differential Hydration of Tricyanomethanide Observed by Time Resolved Vibrational Spectroscopy
The degenerate transition corresponding to asymmetric stretches of the D-3h tricyanomethanide anion, C(CN)(3)(-), in aqueous solution was investigated by linear FTIR spectroscopy, femtosecond pump probe spectroscopy, and 2D IR spectroscopy. Time resolved vibrational spectroscopy shows that water induces vibrational energy transfer between the degenerate asymmetric stretch modes of tricyanomethanide. The frequency frequency correlation function and the vibrational energy transfer show two significantly different ultrafast time scales. The system is modeled with molecular dynamics simulations and ab initio calculations. A new model for theoretically describing the vibrational dynamics of a degenerate transition is presented. Microscopic models, where water interacts axially and radially with the ion, are suggested for the transition diploe reorientation mechanism.