FOURIER-TRANSFORM INFRARED-EMISSION SPECTROSCOPY OF THE C-4-DELTA-X-4-PHI SYSTEM OF ZRCL

The high-resolution spectrum of ZrCl has been investigated in emission in the region 3000-10 000 cm(-1) using a Fourier transform spectromet er. The bands were excited in a microwave discharge through a flowing mixture of ZrCl4, and helium. New ZrCl bands observed in the interval 3600-4400 cm(-1) have been assigned to a new C-4 Delta-X-4 Phi electro nic transition. Four bands with R heads at 4305.7, 4208.0, 4064.7, and 3897.4 cm(-1) have been assigned as the 0-0 bands of the (4) Delta(1/ 2)-(4) Phi(3/2),(4) Delta(3/2)-(4) Phi(5/2), (4) Delta(5/2)-(4) Phi(7/ 2), and (4) Delta(7/2)-(4) Phi(9/2) subbands. A rotational analysis of the 0-0, 1-1, and 2-2 vibrational bands of the four subbands has been obtained and molecular constants have been extracted. Although there is no proof that the lower (4) Phi, State is the ground state of ZrCl, we have labeled this transition as C-4 Delta-X-4 Phi, consistent with the corresponding near-infrared transition of TiCl (R. S. Ram and P. F. Bernath, J. Mel. Spectrosc., in press). (C) 1997 Academic Press.