Dynamical aspects of water by low-frequency Raman scattering
1995; Elsevier BV; Volume: 65-66; Linguagem: Inglês
10.1016/0167-7322(95)00851-8
ISSN1873-3166
AutoresYasunori Tominaga, Yan Wang, Aiko Fujiwara, Kohji Mizoguchi,
Tópico(s)Thermodynamic properties of mixtures
ResumoDepolarized Raman spectra below 250 cm−1 in liquid water (H2O, D2O and H218O), aqueous electrolyte solutions (LiCl, NaCl, KCl, RbCl, MgCl2 and CaCl2), d-glucose solution and ascorbic acid isomerism solutions (l-xylo and d-arabo) were investigated. The Raman spectra below 250 cm−1 in these liquids are interpreted with a superposition of two damped harmonic oscillators and one Debye type relaxation mode (liquid water) or one Cole-Cole type relaxation mode (aqueus solutions). (1) With increasing temperature the half width of half maximum of the central component g1 in H2O has a small bend at about 20°C. (2) For aqueous electrolyte solutions, with increasing salt concentration the ratio of relaxation time τ/τwater shows just the same behavior as the ratio of viscosity η/ηwater. (3) In glucose solution the characteristic frequencies of two oscillator modes do not show any change. This means that the glucose can just embed in the dynamical structure of water. (4) The effect of L-xylo ascorbic acid (Vitamin C) on the dynamical structure of water is different from the effect of D-arabo ascorbic acid.
Referência(s)