FOURIER-TRANSFORM EMISSION-SPECTROSCOPY OF THE A(1)SIGMA(-X(1)SIGMA(+) SYSTEM OF YN())

The electronic emission spectrum of YN has been observed in the 2.3-2. 6 mum spectral region using a Fourier transform spectrometer. The band s were excited in a yttrium hollow cathode lamp in the presence of a t race of molecular nitrogen. The observed bands, with origins at 3882.7 625(4), 4229.0457(3), 4528.6562(46), 4798.5145(13), 5049.4429(20), and 5281.2129(27) cm-1, have been assigned as the 0-0, 1-1, 2-2, 3-3, 4-4 , and 5-5 vibrational bands, respectively, of the A1SIGMA+-X1SIGMA+ el ectronic transition. The principal equilibrium constants for the groun d state obtained from this analysis are B''e = 0.42815(24) cm-1 and r' 'e = 1.80405(50) angstrom, and the corresponding excited state values are B'e = 0.42311(30) cm-1 and r'e = 1.81477(64) angstrom. This work r epresents the first observation of the YN molecule. (C) 1994 Academic Press. Inc.