Accession Number : AD0765734

Title :   Geometry and Vibrational Spectra of the Alkaline Earth Dihalides. III. MgCl2, CaCl2, SrCl2 and BaCl2.

Descriptive Note : Technical rept.,

Corporate Author : PENNSYLVANIA UNIV PHILADELPHIA DEPT OF CHEMISTRY

Personal Author(s) : White,David ; Calder,G. V. ; Hemple,S.

Report Date : 15 AUG 1973

Pagination or Media Count : 30

Abstract : The infrared spectra of MgCl2, CaCl2, SrCl2 and BaCl2 trapped in solid krypton matrices at 20K are reported. From precise measurements of changes in the vibrational modes on isotopic substitution, a linear configuration for MgCl2 and CaCl2 is confirmed and an apex angle of 120 degrees is established for SrCl. For BaCl2 the bond angle has been estimated at 100 degrees. Using a valence force field a set of force constants has been obtained from the measured fundamental frequencies as well as approximate values for the anharmonic corrections to some of the vibrational modes. The statistical entropies calculated from the vibrational frequencies and molecular geometries are in excellent agreement with the thermodynamic measurements. (Author)

Descriptors :   (*ALKALINE EARTH COMPOUNDS, *MOLECULAR STRUCTURE), (*INFRARED SPECTRA, ALKALINE EARTH COMPOUNDS), CHLORIDES, KRYPTON, MOLECULAR STRUCTURE, MOLECULAR ENERGY LEVELS, ENTROPY, FREQUENCY SHIFT, BARIUM COMPOUNDS, CALCIUM COMPOUNDS, MAGNESIUM COMPOUNDS, STRONTIUM COMPOUNDS, ISOTOPES

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE