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CF- anion is very important for collisional ionization reactions, electron transfer from Rydberg atoms and electron attachment. Potential energy curves (PECs) of five low-lying excited electronic states, X3Σ-, a1Δ, b1Σ+, A3Π and c31Π of CF-, are calculated by using the internally contracted multireference configuration interaction (icMRCI) approach. Ro-vibrational levels of these electronic states are derived through solving the radial Schrödinger ro-vibrational equation, and then the molecular parameters are obtained by fitting. Our results for X3Σ- agree well with those in the references. We compute the electronic dipole moments (EDMs) of these states with different bound lengths, and analyze the relationship between the electronic configurations and EDMs. The electronic transition dipole moment matrix elements, Franck-Condon factors and oscillator strengths f00 of A3Π-X3Σ- are evaluated, and radiative lifetimes of five lowest vibrational levels of A3Π state are derived. Finally the predissociation mechanism of A3Π state is discussed in detail, and the dissociation lifetimes of high vibrational levels are obtained.

The high-resolution absorption spectrum of CH4 at 1.51 μm is observed by direct absorption spectroscopy technique with a White absorption cell. Multi-peak fitting technique is adopted to reveal line positions and line intensities of CH4 from 6608 cm−1 to 6625 cm−1. Special attention is paid on the determination of the line positions, and the accuracy is better than ±0.002 cm−1. A minimum measurable absorption of 2.1×10−8 (3σ) has been achieved based on the measured direct absorption spectroscopy.

Fifteen new absorption lines are observed when studying CO2 absorption spectroscopy by wavelength modulation (WM) technique with a distributed feedback laser. The overtone spectra of CO2 around 1.31 μm and the corresponding spectral parameters (i.e. positions, intensities, self-broadening coefficients) are presented. The intensity of the weakest line detected is 2.25163×10−27 cm−1/(molecule.cm−2) at the pressure of 5 Torr, with a corresponding absorption of 3.88×10−8.

The absorption spectrum of NO is analyzed in a range of 12530-12850 cm-1 using optical heterodyne concentration modulation spectroscopy in an AC glow discharge of He/NO mixture. Among all the spectral lines, 324 lines are assigned to the (4, 0) band and 267 ones are fitted to the Hamiltonians of the b4Σ--a4Πi system by a non-linear least-square fitting procedure. A residual (0.0071 cm-1) comparable to system error (0.0071 cm-1) is obtained. The main molecular constants are consistent with those reported in the literature and the fine structure constants are fitted.