Rotational analysis of the 301 band of the (A)over-tilde6Σ ← (X)over-tilde6Σ system of CrCCH

The spectrum of chromium acetylide, CrCCH, has been investigated in the near-infrared region (10 500-14 500 cm(-1)) and an intense band system is observed. The 310 band of this system has been investigated at high resolution (0.025 cm(-1)) and this system is identified as the (A) over tilde (6)Sigma(+) <- (X) over tilde (6)Sigma(+) system, analogous to the near IR spectra of the CrH, CrF, and CrCl molecules. Among the many unidentified lines, we have assigned 341 lines belonging to 43 of the 54 allowed branches. Using combination differences, the rotational constants of the ground state have been determined. Computational results on the ground state are also reported, along with a comparison to other monoligated monovalent chromium compounds. (C) 2014 AIP Publishing LLC.