Experimental Determination of Relationship between Intramolecular O-D Bond Length and Its Stretching Vibrational Frequency of D2O Molecule in the Liquid State

Experimental evidence has been obtained for the structure-spectra relationship of hydrogen bonds in aqueous solutions. Intramolecular O-D distance, r(OD), has been determined by the least-squares fitting analysis of the neutron interference term in the high-Q region observed for pure D2O and concentrated aqueous solutions. The average O-D stretching frequency, nu(OD), has been obtained from the position of the center of gravity of the observed ATR-IR O-D stretching band. The linear relationship between r o r(OD) and nu(OD) has been confirmed in the liquid state. The slope of d nu(OD)/dr(OD) is evaluated to be -21 000 +/- 1000 cm(-1) A(-1).