The state-to-state vibrational predissociation (VP) dynamics of the hydrogen-bonded ammonia-water dimer were studied following excitation of the bound OH stretch. Velocity-map imaging (VMI) and resonance-enhanced multiphoton ionization (REMPI) were used to determine pair-correlated product energy distributions. Following vibrational excitation of the bound OH stretch fundamental, ammonia fragme...

Experimental studies of underexpanded nitrogen jets [1], [2] discovered a delay of the rotational temperature TR compared to the translational one Tt in the expanding supersonic flow. The combined effect of the R-T relaxation, viscosity and thermal conductivity was analyzed by Riabov [3], [4], Lebed and Riabov [5], and Skovorodko [6]. A significant drop in the gas density downstream leads to a ...

The state-to-state vibrational predissociation dynamics of the hydrogen-bonded HCl-H(2)O dimer were studied following excitation of the HCl stretch of the dimer. Velocity-map imaging and resonance-enhanced multiphoton ionization (REMPI) were used to determine pair-correlated product energy distributions. Following vibrational excitation of the HCl stretch of the dimer, HCl fragments were detect...

The present symposium brings together research in a number of fields: the quantum-chemical calculation of molecular potential-energy surfaces, rotational-vibrational spectroscopy, methods of calculating rotational-vibrational energy levels, unimolecular reactions and intramolecular dynamics. Several aspects of the work are discussed, including some recent developments on rates and products' qua...

Total rotational energy transfer rates have been measured at 1330 K for specific rotational levels in the OH A2X +, v' = 0 state in collisions with H20. Rotational levels ranging from N' = 0 to 15 were studied. Measurements were performed in the post-flame region of a stoichiometric H2/O2/He flame operating at 25 mbar. Quenching rates following excitation of individual upper rotational states w...

Vibration-rotation and pure rotational data in the X2Σ+ ground state and electronic data from the A2Π – X2Σ+ and B2Σ+ − X2Σ+ transitions of CaH and CaD were used in the quantum-mechanical direct-potential-fit (DPF) analysis to determine an analytic potential energy function for the X2Σ+ ground state of CaH, and a radial correction function for the CaD isotopologue. The potential energy function...

Previous experimental and theoretical studies of the radical dissociation channel of T(1) acetaldehyde show conflicting behavior in the HCO and CH(3) product distributions. To resolve these conflicts, a full-dimensional potential-energy surface for the dissociation of CH(3)CHO into HCO and CH(3) fragments over the barrier on the T(1) surface is developed based on RO-CCSD(T)/cc-pVTZ(DZ) ab initi...

Rotational effects in the dissociative adsorption of H2 on the Pt211 stepped surface have been studied using classical trajectory calculations on a six-dimensional, density-functional theory potential-energy surface. Reaction of rotating molecules via an indirect trapping mechanism exhibits an unexpected nonmonotonic dependence on the initial rotational quantum number J. Indirect reaction is fi...

The rotational spectrum of 1-benzofuran has been investigated by three different rotational spectroscopy techniques: (i) millimeterwave absorption free jet spectroscopy, useful for a fast assignment of the spectrum; (ii) molecular beam Fourier transform microwave spectroscopy, sensitive to detect less abundant isotopic species in natural abundance; (iii) waveguide conventional microwave spectro...

We present cross sections for rotational, vibrational, and fine-structure transitions in He–CaH(S) collisions at cold and ultracold temperatures calculated using the ab initio potential energy surface reported in the preceding paper. Rotational quenching is fast, vibrational quenching is slow. The spin-rotational interaction, although small and having no influence at temperatures above 10 K, ch...