title: Energy relaxation versus spectral diffusion of the OH-stretching vibration of HOD in liquid-to-supercritical deuterated water.
abstract: The dynamics of vibrational energy relaxation (VER) of the OH-stretching vibration of HOD in liquid-to-supercritical heavy water is studied as a function of temperature and solvent density by femtosecond mid-infrared spectroscopy. Using the dielectric constant of the fluid both, the OH-stretching absorption frequency and the VER rate, can be correlated phenomenologically with the average hydrogen-bond connectivity within the random D2O network. This correlation enables the identification of thermodynamic conditions under which spectral diffusion due to hydrogen-bond breakage/formation is much faster than VER.
authors.affiliation: Max-Planck-Institut für biophysikalische Chemie, Abteilung Spektroskopie und Photochemische Kinetik, Am Fassberg 11, 37077 Göttingen, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Schwarzer
authors.forename: Jörg
authors.initials: J
authors.lastname: Lindner
authors.forename: Peter
authors.initials: P
authors.lastname: Vöhringer
mesh_terms: D002627:Chemistry, Physical / Q000379:methods*; D003903:Deuterium / Q000737:chemistry*; D004058:Diffusion; D006860:Hydrogen Bonding; D006878:Hydroxides / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013055:Spectrophotometry, Infrared / Q000379:methods; D013057:Spectrum Analysis / Q000379:methods; D013696:Temperature; D013816:Thermodynamics; D014867:Water / Q000737:chemistry*
chemical_list: D006878:Hydroxides; D012997:Solvents; D014867:Water; C031356:hydroxide ion; D003903:Deuterium