Identification of a wagging vibrational mode of water molecules at the water/vapor interface.
An improved time correlation function description of sum frequency generation (SFG) spectroscopy was applied to theoretically describe the water/vapor interface. The resulting spectra compare favorably in shape and relative magnitude to extant experimental results in the O-H stretching region of water. Further, the SFG spectra show a well-defined intermolecular mode at 875 cm(-1) that has significant intensity. The resonance is due to a wagging mode localized on a single water molecule. It represents a well-defined population of water molecules at the interface that, along with the free O-H modes, represent the dominant interfacial species.
Perry
Angela
A
Department of Chemistry, University of South Florida, 4202 E. Fowler Ave., SCA400, Tampa, FL 33620-5250, USA.
Neipert
Christine
C
Ridley
Christina
C
Space
Brian
B
Moore
Preston B
PB