Overtone spectroscopy of molecular complexes containing small polyatomic molecules

Abstract

The literature on the high-resolution spectroscopic investigation of molecular complexes containing small polyatomic species excited in their vibrational overtones is reviewed. They turn out to be complexes containing acetylene, ammonia and water, mainly excited in their 2CH, 2NH and 2OH vibrations, respectively. The majority of results published on these systems was obtained using an instrumental set-up based on cw-cavity ring-down spectroscopy, built in the 'Laboratoire de Chimie quantique et Photophysique' at the 'Université libre de Bruxelles' (CQP/ULB) and named FANTASIO+, which is described. It allowed retrieving upper state vibrational predissociation lifetimes, which are highlighted together with more results. The sequence of experiments at CQP/ULB prior and along the line of those supporting the investigation of molecular complexes is briefly illustrated.

Computational Fluid Dynamic simulation of the supersonic CO2 expansion during champagne cork popping

“…The free jet can then reach very high Mach numbers, which corresponds to high speeds but also to temperatures which can be extremely low, close to absolute zero, 7 under the law of conservation of energy. This speci city of supersonic ows is used in particular to carry out studies of chemical reactivity 8 or spectroscopy 9 at very low temperature in the gas phase. The interaction of the supersonic free jet with the downstream static gas leads to the formation of a complex network of shock waves and boundary layers, also called diamond shocks by Ernst Mach who rst described them using shadowgraphy.…”

Characterization of OCS–HCCCCH and N2O–HCCCCH Dimers: Theory and Experiment

“…Acetylene is a prototype molecule for examining weak intermolecular forces involving carbon–carbon triple bond. Pure and mixed acetylene clusters have been studied extensively both theoretically and experimentally. − In particular, mixed dimers containing OCS and N 2 O with acetylene are well characterized using microwave and infrared spectroscopy. To date, only one isomer of N 2 O–HCCH has been observed in the gas phase. ,, This isomer, which is almost certainly the most stable structure, is planar with near parallel monomer units.…”

Characterization of Ocs-HCCCCH and N2o-HCCCCH Dimers: Theory and Experiment

“…Acetylene is a prototype molecule for examining weak intermolecular forces involving carbon-carbon triple bond. Pure and mixed acetylene clusters have been studied extensively both theoretically and experimentally [1,2,3,4]. In particular, mixed dimers containing OCS and N 2 O with acetylene are well characterized using microwave and infrared spectroscopy.…”