New Band Systems of the YbCl Molecule.

The thermal emission spectrum of the YbCl molecule, lying in the 3800-6000 A region, has been photographed for the first time at a reciprocal linear dispersion of 7.3 A/mm. More than 196 violet degraded bands have been recorded on a 2-m plane grating spectrograph in first order and assigned to the vibrational schemes of six systems, viz. A, B1, B2, C1, C2, and D. While the systems A, C1, C2, and D consist of single headed bands, the systems B1 and B2 consist of double headed bands. The vibrational analysis performed suggests that these systems arise from the ground state (2Sigma+) of YbCl molecule. The systems C1-X, C2-X, and D-X have been analyzed for the first time. More precise vibrational constants for the relevant states have been determined. Copyright 1997 Academic Press. Copyright 1997Academic Press