We report the recent progress in the performance of the CO-overtone Δv=2 laser. We were able to increase both the number of lines and the output power by a significant amount. This laser is now a reliable source for spectroscopic applications in the spectral region from 2500–3800 cm−1. The typical parameters of the laser plasma and a table with the observed laser transitions and their frequencies are given.

Heterodyne frequency measurements have been extended to 87 THz by using the CO overtone laser as a transfer oscillator. Measurements were made on the 1111-0110 band of OCS at 2900 cm−1. Frequency differences were measured between a tunable diode laser (TDL) which was locked to OCS absorption lines and a stabilized overtone laser which was referenced to stabilized CO2 lasers. These measurements have been combined with earlier Fourier transform (FT) measurements and a comprehensive set of data from frequency and FT measurements on lower lying transitions in OCS. This permits obtaining accurate values of transition frequencies for calibration of spectra in the 3.4-μm region.

We report the first direct observation of pure fine structure transitions of the diatomic nickel hydride radical in its X2-DELTA ground state. Using CO2-Faraday laser magnetic resonance spectroscopy (LMR) we could observe the spin forbidden rotational transitions P(2.5), P(3.5), P(4.5) between the sub states X2-DELTA(5/2)(upsilon" = 0) and X2-DELTA(3/2)(upsilon' = 0). The experimental data permitted us to determine the spin-orbit constant A to a very precise value. Completing previous work, the NiH X2-DELTA ground state is now well described by a suitable set of molecular parameters.

We report the first direct gas phase observations of the electronic transitions, 2-DELTA-5/2, upsilon = 0 --> 2-PI-3/2, upsilon = 0 and 2-DELTA-5/2, upsilon = 0 --> 2-DELTA-3/2, upsilon = 1, in the NiH radical. NiH radical. From the observed transitions we obtained transition frequencies and electronic g factors.The observation of these electronic transitions by LMR has been possible only by employing the recently developed CO overtone laser. This work forms the first spectroscopic application of this new laser.

We report the first direct gas phase observations of the electronic transitions, 2Δ5/2, ν = 0 → 2Π3/2, ν = 0 and 2Δ5/2, ν = 0 → 2Δ3/2, ν = 1, in the NiH radical. From the observed transitions we obtained transition frequencies and electronic g factors. The observation of these electronic transitions by LMR has been possible only by employing the recently developed CO overtone laser. This work forms the first spectroscopic application of this new laser.

We report the first direct observation of the vibration-rotation spectrum of nickel-deuteride in its X 2Δ ground state by CO-Faraday-L.M.R. spectroscopy. A set of effective molecular parameters is given. We present first results on the vibration-rotation spectroscopy of NiH, employing a tunable diode laser spectrometer.

We report the first direct observation of the vibration-rotation spectrum of the diatomic chromium-hydride in its X6-SIGMA+ ground state by CO-Faraday laser magnetic resonance spectroscopy (LMR). Transitions of all four isotopomers attributed to the fundamental and the first hot band were detected. The spectra were analysed by a single least-squares fit using an effective Hamiltonian. A set of effective molecular parameters for the X6-SIGMA+ ground state is given.

We report the first spectroscopic observation of the tin hydride radical in the infrared spectral region. Vibration rotation transitions of the ten stable isotopic forms of SnH in the 2п3/2 component of its ground state were recorded with a CO-LMR-spectrometer. The isotopic structure, the ∧-doubling in the 2п3/2 substate and the hyperfine splitting due to the tin isotopes 115Sn, 117Sn and 119Sn have been resolved for the first time. A set of effective molecular parameters of the X 2п3/2 state is given.

We present the first spectroscopic observation of the nickel-hydride free radical in the infrared region in the gas phase. A set of vibrational rotational molecular constants for the electronic ground state is given.