Search results for "Rotational States"

showing 3 items of 3 documents

Study of the benzene⋅N2 intermolecular potential-energy surface

2003

The intermolecular potential-energy surface pertaining to the interaction between benzene and N2 is investigated theoretically and experimentally. Accurate intermolecular interaction energies are evaluated for the benzene–N2 van der Waals complex using the coupled cluster singles and doubles including connected triples [CCSD(T)] method and the aug-cc-pVDZ basis set extended with a set of 3s3p2d1f1g midbond functions. After fitting the energies to an analytic function, the intermolecular Schrödinger equation is solved to yield energies, rotational constants, and Raman-scattering coefficients for the lowest intermolecular levels of several benzene–N2 isotopomers. Experimentally, intermolecula…

Potential Energy SurfacesCoupled Cluster CalculationsNitrogenBinding energyGeneral Physics and AstronomyPotential Energy Functionssymbols.namesakePhysics and Astronomy (all)IsomerismQuasimoleculesRotational IsomerismPhysics::Atomic and Molecular ClustersQuantum-mechanical explanation of intermolecular interactionsRotational StatesPhysical and Theoretical ChemistryPhysics::Chemical Physics:FÍSICA::Química física [UNESCO]Basis setSchrodinger EquationChemistryOrganic CompoundsIsotope EffectsIntermolecular forceStimulated Raman ScatteringUNESCO::FÍSICA::Química físicaCoupled clustersymbolsAtomic physicsvan der Waals forceOrganic Compounds ; Nitrogen ; Quasimolecules ; Potential Energy Surfaces ; Potential Energy Functions ; Coupled Cluster Calculations ; Rotational States ; Isomerism ; Isotope Effects ; Stimulated Raman Scattering ; Rotational Isomerism ; Schrodinger EquationRaman spectroscopyRaman scattering
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Computational and experimental investigation of intermolecular states and forces in the benzene-helium van der Waals complex

2003

A study of the intermolecular potential-energy surface (IPS) and the intermolecular states of the perprotonated and perdeuterated benzene–He complex is reported. From a fit to ab initio data computed within the coupled cluster singles and doubles including connected triples model for 280 interaction geometries, an analytic IPS including two- to four-body atom–atom terms is obtained. This IPS, and two other Lennard-Jones atom–atom surfaces from the literature, are each employed in dynamically exact (within the rigid-monomer approximation) calculations of J = 0 intermolecular states of the isotopomers. Rotational constants and Raman-scattering coefficients for intermolecular vibrational trans…

Potential Energy SurfacesCoupled Cluster CalculationsRaman SpectraHelium Neutral AtomsOrganic Compounds ; Helium Neutral Atoms ; Intermolecular Mechanics ; Quasimolecules ; Potential Energy Surfaces ; Ab Initio Calculations ; Coupled Cluster Calculations ; Lennard-Jones Potential ; Isotope Effects ; Isomerism ; Rotational States ; Raman SpectraAb initioGeneral Physics and AstronomyIsotopomerssymbols.namesakePhysics and Astronomy (all)IsomerismAb initio quantum chemistry methodsQuasimoleculesKinetic isotope effectPhysics::Atomic and Molecular ClustersRotational StatesPhysics::Atomic PhysicsLennard-Jones PotentialPhysics::Chemical PhysicsPhysical and Theoretical Chemistry:FÍSICA::Química física [UNESCO]ChemistryOrganic CompoundsIsotope EffectsIntermolecular forceUNESCO::FÍSICA::Química físicaCoupled clusterLennard-Jones potentialsymbolsIntermolecular MechanicsAtomic physicsvan der Waals forceAb Initio Calculations
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Raman spectroscopy and crystal-field split rotational states of photoproducts CO and H2 after dissociation of formaldehyde in solid argon

2012

Raman signal is monitored after 248 nm photodissociation of formaldehyde in solid Ar at temperatures of 9–30 K. Rotational transitions J = 2 ← 0 for para-H2 fragments and J = 3 ← 1 for ortho-H2 are observed as sharp peaks at 347.2 cm−1 and 578.3 cm−1, respectively, which both are accompanied by a broader shoulder band that shows a split structure. The rovibrational spectrum of CO fragments has transitions at 2136.5 cm−1, 2138.3 cm−1, 2139.9 cm−1, and 2149 cm−1. To explain the observations, we performed adiabatic rotational potential calculations to simulate the Raman spectrum. The simulations indicate that the splitting of rotational transitions is a site effect, where H2 molecules can resi…

Raman spektroskopiacarbon compoundstranslational statesphotodissociationmatriisi-isolaatiohydrogen neutral moleculesrotational statesrotational-vibrational statesfotodissosiaatiorotaatio-vibraatiotilatmolecule-photon collisionsRaman spectrainterstitialsorgaaniset yhdisteet
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