THE A(2)SIGMA (+)-X(2)PI BANDS OF (OH)-O-18

The emission spectrum of the A(2) Sigma(+)-X(2) Pi (0,0), (1,0), and (1,1) bands of (OH)-O-18 has been investigated with a 6.65-m vacuum spectrograph in the wavelength region from 290 to 350 nm. The emission spectrum of (OH)-O-18 was produced by microwave discharge of H-2 O-18 vapor. In the (0,0) and (1,0) bands, all 12 branches expected for a (2) Sigma(+)-(2) Pi transition have been observed and assigned, but only 10 branches have been identified and assigned in the weaker (1,1) band. A merged least-squares fit of the measured line positions yielded molecular parameters of both the A(2) Sigma(+) and the X(2) Pi states. Good agreement has been obtained between determined molecular parameters and those calculated from isotopic relationships. (C) 1995 Academic Press, Inc.