THE A (1)DELTA (A2) STATE OF BIF

The electronic states and spectra of the bismuth monofluoride radical have been studied by LIF and Fourier-transfonn spectrometry. With lase r excitation of the Omega=1 states A(3)1 and C(3)1, fluorescence spect ra of the transitions A(3)1 --> X(1)0(+), A(3)1 --> X(2)1, A(3)1 --> a 2 and C(3)1 --> X(1)0(+), C(3)1 --> a2 were observed. Some bands of th e C(3)1 --> a2 system were measured at medium spectral resolution with the FT spectrometer. Analysis of the spectra yielded the following mo lecular constants of the a2 state (in cm(-1)): T-e = 12076.7 +/- 1, om ega(e) = 536.2, omega(e)x(e) = 2.30. The a2 state of BiF is found to b e populated in the reaction of Bi-x vapour with F-2 and by near-resona nt electronic energy transfer from metastable NF(a (1) Delta) molecule s.