Probing the intermolecular hydrogen bonding of water molecules at the $CCl4$/water interface in the presence of charged soluble surfactant

The molecular structure and hydrogen bonding of water molecules at the $CCl4$/water interface in the presence of a charged soluble surfactant has been explored in this study using vibrational sum frequency generation. By examining OH stretching modes that are highly sensitive to the local hydrogen bonding environment it is found that water molecules at the $CCl4$/water interface both in the presence and absence of a charged soluble surfactant are predominantly in a tetrahedral arrangement much like the structure of ice. Isotopic dilution studies have been employed to further characterize this icelike interfacial structure. A blueshift of approximately 120 $cm−1$ of the icelike OH stretching mode is observed upon dilution with $D2O.$ The first vibrational spectra of the OH stretching mode from uncoupled HOD molecules at the $CCl4$/water interface is also reported.