HIGH-RESOLUTION LASER SPECTROSCOPY OF EXCITED BENDING VIBRATIONS (UPSILON(2)LESS-THAN-OR-EQUAL-TO-2) OF THE (B)OVER-TILDE(2)SIGMA-TILDE(2)SIGMA+ ELECTRONIC STATES OF SROH - ANALYSIS OF L-TYPE DOUBLING AND L-TYPE RESONANCE( AND (X)OVER)

The (2(0)0)SIGMA+ <-- (000)SIGMA+, (02(2)0)DELTA <-- (010)PI, (02(0)0) SIGMA+, and (010)PI, and (010)PI <-- (000)SIGMA+ bands in the B2SIGMA <-- X2SIGMA+ electronic system of SrOH have been recorded at Doppler limited resolution using CW dye laser excitation with selective detect ion. Fluorescence from selected rotational levels of the B2SIGMA+(02(0 )0)SIGMA+ and B2SIGMA+)02(2)0)DELTA vibronic states has been dispersed , providing access to the (02(0)0)SIGMA+ and (02(2)0)DELTA levels of t he ground electronic state. Over 1200 line positions from all transiti ons were included in a global least-squares fit. The effects of a weak l-type resonance between the l = 0 and l = 2 components of the upsilo n2 = 2 vibrational level were observed in both electronic states and t he off-diagonal matrix elements were evaluated in a case (b) basis. A previous analysis of the B2SIGMA+(010)PI level that attributes the ano malous l-type doubling to an electronic perturbation arising from the A2PI(010) polyad is inconsistent with our experimental results.