High resolution infrared emission spectra of GaH and GaD.

The high resolution infrared emission spectra of gallium hydride and gallium deuteride have been recorded with a Fourier transform spectrometer. There were 1045 lines observed including those from the v=1→0 to v=7→6 bands for the 69GaD and 71GaD species and v=1→0 to v=4→3 bands for the 69GaH and 71GaH species. Dunham Yij’s for each isotopomer were obtained by fitting the data set of each isotopomer separately to the Dunham energy levels of the X 1Σ+ electronic ground state. The mass-reduced Dunham Uij’s were determined using two independent methods. In the first fit the Uij’s constants were determined by the traditional method where all the constants were treated as adjustable parameters and determined statistically. In the second fit the Uij’s which satisfied the condition j<2 were treated as adjustable parameters and the remaining constants were fixed by constraints imposed by the Dunham model. In order to predict the positions of transitions with v’s and J’s much higher than those observed the entire data set was fit directly to the eigenvalues of the Schrödinger equation containing a parameterized internuclear potential energy function. [ABSTRACT FROM AUTHOR]