FOURIER-TRANSFORM INFRARED-EMISSION SPECTROSCOPY OF NACL AND KCL

The infrared emission spectra of NaCl and KCl have been recorded at hi gh resolution with a Fourier transform spectrometer, A total of 929 Li nes belonging to 8 vibrational bands, 1-0 to 8-7, for (NaCl)-Cl-35, 25 2 lines of 1-0, 2-1, and 3-2 bands of (NaCl)-Cl-37, and 355 lines of 1 -0, 2-1, 3-2, and 4-3 bands of (KCl)-Cl-35 have been measured and comb ined with the existing microwave and millimeter-wave data to obtain a set of refined molecular constants. The data for (NaCl)-Cl-35 and (NaC l)-Cl-37 have also been fitted to determine the Dunham Y-ij constants and mass-reduced Dunham constants U-ij. In one fit all U-ij's were tre ated as adjustable parameters while in a second fit only U-10's and U- 11's were allowed to vary freely with the remaining U-ij constants det ermined by the constraints imposed by the Dunham model. In addition, t he internuclear potential energy parameters were determined by fitting the entire NaCl data set to the eigenvalues of the Schrodinger equati on containing a parameterized potential energy function. (C) 1997 Acad emic Press.