High-resolution infrared spectra of (NCCN)-N-15-C-12-C-12-N-15 and N-14 (CCN)-C-13-C-13-N-14

High-resolution spectra of (NCCN)-N-15-C-12-C-12-N-15 and (NCCN)-N-14-C-13-C-13-N-14 have been measured and analyzed from 200 to 3600 cm(-1). All the vibrational levels below 900 cm(-1) have been observed and characterized. The Fermi resonance between nu(2) and 2nu(4) has been studied and the resonance constant has been determined for several cases. Several Sigma(-) states have been directly observed for the first time for each isotopomer, the (0001(1)1(1))(0f), (0011(1)1(1))(0f), and (0002(2)2(2))(0f) states. The pattern of the energy levels for clusters of l-type resonance coupled levels, such as 0 0 0 1(1)3(1,3), has been determined for cyanogen for the first time. Among other things this involved the determination of the vibrational l-type resonance constant, r(45). Many of the power series constants, alpha(i) and x(ij), and higher order constants have been determined. (C) 2003 Elsevier Inc. All rights reserved.