ROTATIONAL ANALYSIS OF THE A 3-SIGMA-X1-SIGMA+ TRANSITION OF CUBR ENHANCED BY TRANSFER FROM LASER-EXCITED B-3-PI-1 STATE()

The new A'(v'=0)-X 1SIGMA+ (v''=0) transition of CuBr, recently observ ed (P. Kowalczyk, 1. Hikmet and N. Sadeghi, Chem. phys. 160 (1992) 73) at 504.5 nm has been rotationally analysed. Different sequences of th is transition are completely overlapped by the bands of the A 3PI-X 1S IGMA+ transition. The intensity of the 0-0 band of the A'-X transition has been enhanced by a selective laser excitation of the 0-0 band of the A-X transition followed by the collisional or/and radiative transf er to the A' state. The analysis of the partially resolved 0-0 band of the A'-X transition confirms the nature 3SIGMA+ of the A' state as ex pected from the comparison with the spectrum of CuF and CuCl. The deri ved spectroscopic constants of this state are (in cm-1) T0=19820.19, B 0'=0.09415, D0'=0.28x10(-7), lambda0'=1.0, gamma0'=0.40. It turns out that, following the conventional notation, the A' 3SIGMA and the A 3PI states are now called a 3SIGMA+ and b 3PI respectively.