INTERNAL AND EXTERNAL FORCE-FIELDS AND NORMAL VIBRATIONS OF THE WATER-MOLECULES IN BA(CLO3)2.H2O AND K2C2O4.H2O

Normal coordinate analyses of the water molecules in Ba(ClO3)2.H2O and K2C2O4.H2O have been made. The water molecules have been allowed to vibrate in an effective force field from stationary surrounding atoms, resulting in nine normal modes. Vibrational data from earlier infrared, Raman and neutron inelastic scattering studies have been used for the determination of the force constants. The OH stretching force constants are 7.80 and 6.97 mdyn Å-1 for the water molecules in Ba(ClO3)2.H2O and K2C2O4.H2O, respectively. The force constants for the rotational vibrations about the principal inertial axes of the water molecules range from 0.052 to 0.48 mdyn Å rad-2 and those for the translational vibrations along these axes from 0.17 to 0.66 mdyn Å-1. © 1979.