Vibrational response of hydrogen-bonded interfacial water is dominated by intramolecular coupling.
Using the surface-specific vibrational technique of vibrational sum-frequency generation, we reveal that the double-peaked structure in the vibrational spectrum of hydrogen-bonded interfacial water molecules originates from vibrational coupling between the stretch and bending overtone, rather than from structural effects. This is demonstrated by isotopic dilution experiments, which reveal a smooth transition from two peaks to one peak, as D2O is converted into HDO. Our results show that the water interface is structurally more homogeneous than previously thought.
Sovago
Maria
M
FOM Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ, Amsterdam, The Netherlands.
Campen
R Kramer
RK
Wurpel
George W H
GW
Müller
Michiel
M
Bakker
Huib J
HJ
Bonn
Mischa
M
D006860:Hydrogen Bonding; D013055:Spectrophotometry, Infrared / Q000379:methods; D013499:Surface Properties; D014867:Water / Q000737:chemistry*
D014867:Water