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We repolt integral cross sections for the collision processes between H(D) atoms and Hz(D2) molecules in the energy range from -hold to 170 eV leading to charged collision products. We observe not only charge exchange and target or projectile ionization such as H + HI + Ht H: and H t Hz + H t e t H : but also associative ionization, H + Hz --L H : t e, and heavy panicle exchange, D t Hz + HD+ + H -. Typical absolute cross section values are belween c d and IO-'' cm'.

The near-infrared electronic spectrum of MoO has been recorded in emission using the Fourier transform spectrometer associated with the National Solar Observatory at Kitt Peak, AZ. The gas phase MoO molecules were produced in a neon-based electric discharge using a molybdenum hollow cathode and a trace amount of oxygen. One MoO molecular band was observed in the spectrum with a red-degraded bandhead at 6735 cm(-1) and is assigned as the (0,0) band of the c (3)Π1 - a (3)Σ(-) 0+ transition. The assignment is based upon isotopologue shifts and ab initio calculations. Results from the ab initio calculations and analysis are presented. The new calculations support the assignment of the observed transition and have led to reassignment of several electronic states from previous work.

Several new vibrational bands of the [12.5] Ω = 0+–X3Σ−Ω=0+ and the [15.9] B Ω = 0+–X3Σ−Ω=0+ transitions have been observed in high resolution absorption measurements recorded using Intracavity Laser Spectroscopy (ILS). These new bands have been rotationally analyzed and incorporated into a comprehensive PtS dataset that was fit to a mass-independent Dunham expression using PGOPHER. The comprehensive dataset included all reported field-free, gas phase spectroscopic data for PtS, including 32 Fourier transform microwave transitions (estimated accuracy: 1 kHz), 9 microwave/optical double resonance transitions (25 kHz), 51 millimeter and submillimeter transitions (25–50 kHz), 469 molecular beam-laser induced fluorescence transitions (0.003 cm−1), and 4870 ILS transitions (0.005 cm−1). The determined equilibrium constants have been used with the Rydberg-Klein-Rees method to produce potential energy curves for the four known electronic states of PtS. Isotopic shifts in electronic transition energy beyond expectations from the Born-Oppenheimer approximation were observed and treated as electronic field-shift effects due to the difference in the nuclear charge radius between Pt isotopes. The magnitude and sign of the determined field-shift parameters are rationalized through the analysis of the previously reported ab initio calculations.

The near-infrared spectrum of nickel chloride, NiCl, has been recorded at high resolution from 12,400-12,600 cm-1 , 13,200-13,500 cm-1 , and 13,600-13,750 cm-1 using intracavity laser absorption spectroscopy, ILS. The NiCl molecules were produced in the plasma discharge of a nickel-lined, copper hollow cathode with ~1.8 torr of Ar as the sputter gas and a trace amount of CCl4 as the chloride source. Several transitions were observed and analyzed, including the (2,0), (1,0), and (0,1) bands of the [13.0] 2 Π3/2-X 2 Π3/2 transition, System G, and the (1,0) band of the [12.3] 2 Σ-X 2 Π3/2 transition, System H. The transitions were analyzed using PGOPHER and obtained molecular parameters are reported. A potential energy curve for the [13.0] 2 Π3/2 state has been constructed using the vibrational information from the analyzed transitions.