A JUMP IN THE POSITION AND WIDTH OF THE RAMAN BAND ENVELOPE OF O-H VALENCE VIBRATIONS UPON PHASE-TRANSITIONS OF THE FIRST AND 2ND KINDS IN WATER

A 150-cm(-1) jump in the position and width of the envelope of the Ram an band of O-H valence vibrations of molecules was found for the first time upon the ice-water phase transition. The continuous temperature shift of the center of the Raman band envelope is described by a linea r law lambda = lambda(o) + kt with the averaged slope k = (1.1 +/- 0.1 ) cm(-1) K-1. Jumps with smaller amplitudes were detected upon phase t ransitions of the second kind at temperatures 4, 17, 37, and 75 degree s C. A correlation of the observed spectral features of the Raman band envelope with evolution of entropy and other thermodynamic parameters is discussed as a new approach to remote Lidar studies of water and i ce.