The high-resolution spectrum of NbN has been investigated in emission in the 3000-15 000 cm(-1) region using a Fourier transform spectrometer, The bands were excited in a microwave discharge through a mixture of NbCl5 vapor, similar to 5 mTorr of N-2, and 3 Torr of He. Numerous bands observed in the near-infrared region have been classified into the following transitions: f(1)Phi-c(1)Gamma, e(1)Pi-a(1)Delta, C(3)Pi(0+)-A(3)Sigma(1)(-), C(3)Pi(0-)-A(3)Sigma(1)(-), C(3)Pi(1)-a(1)Delta, C(3)Pi(1)-A(3)Sigma(0)(-), d(1)Sigma(+)-A(3)Sigma(0)(-), and d(1)Sigma(+)-b(1)Sigma(+). These observations are consistent with the energy level diagram provided by laser excitation and emission spectroscopy [Y. Azuma, G. Huang, M, P. J. Lyne, A. J. Merer, and V. I. Srdanov, J. Chem. Phys. 100, 4138-4155 (1993)]. The missing d(1)Sigma(+) state has been observed for the first time and its spectroscopic parameters are consistent with the theoretical predictions of S. R. Langhoff and W. Bauschlicher, Jr. [J. Mel. Spectrosc. 143, 169-179 (1990)]. Rotational analysis of a number of bands has been obtained and improved spectroscopic parameters have been extracted for the low-lying electronic states. The observation of several vibrational bands with nu = 1 has enabled us to determine the vibrational intervals and equilibrium bond lengths for the A(3)Sigma(0)(-), a(1)Delta, b(1)Sigma(+), d(1)Sigma(+), and C(3)Pi(1) states. (C) 2000 Academic Press.
|Number of pages||13|
|Journal||JOURNAL OF MOLECULAR SPECTROSCOPY|
|Publication status||Published - Jun 2000|
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