χ(4) Raman spectroscopy for buried water interfaces

Abstract

π-Type H-bonds that are not found in bulk liquid phases, where σ-type H-bonds prevail, were detected for the dye rhodamine 800 at air/water and fused silica/water interfaces (see picture) by interface-selective fourth-order nonlinear (χ(4)) Raman spectroscopy in the frequency domain. This new method allows vibrational spectra of organic solutes at liquid interfaces to be obtained in the whole fingerprint region (200-2800 cm-1). (Figure Presented). © 2007 Wiley-VCH Verlag GmbH & Co. KGaA.