0000000000407740

AUTHOR

Pierre Labéguerie

showing 2 related works from this author

Theoretical investigations of the IR spectroscopy of Ni(C(2)S(2)H(2))(2). A case study of the P_VMWCI(2) algorithm including anharmonic effects.

2010

The near infrared (NIR) spectra of bis(ethylene-1,2-dithiolato)nickel, Ni(C(2)S(2)H(2))(2) are fully interpreted here by applying a method developed for efficient automatic computation of both the infrared wave numbers and the intensities. The employed procedure uses parallel variational multiple window configuration interaction wave functions, the so-named P_VMWCI(2) algorithm, which incorporates both the mechanical and the electric anharmonic effects. It is shown that inclusion of anharmonicities is crucial for correctly assigning the fundamental, combination, and overtone vibrational frequencies in the infrared spectrum of the target system, for which conflicting assignments are found in…

Spectrophotometry InfraredInfraredChemistryOvertoneAnharmonicityNear-infrared spectroscopyGeneral Physics and AstronomyInfrared spectroscopyConfiguration interactionModels TheoreticalSpectral lineCoordination ComplexesNickelPhysics::Chemical PhysicsPhysical and Theoretical ChemistryWave functionAlgorithmAlgorithmsPhysical chemistry chemical physics : PCCP
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Linear and nonlinear optical properties of a series of Ni-dithiolene derivatives

2009

Some linear and nonlinear optical (NLO) properties of Ni(SCH)4 and several of its derivatives have been computed by employing a series of basis sets and a hierarchy of methods (e.g., HF, DFT, coupled cluster, and multiconfigurational techniques). The electronic structure of Ni(SCH)4 has been also analyzed by using CASSCF/CASPT2, ab initio valence bond, and DFT methods. In particular we discuss how the diradicaloid character (DC) of Ni(SCH)4 significantly affects its NLO properties. The quasidegeneracy of the two lowest-energy singlet states 1 mathg and 1 math1u, the clear DC nature of the former, and the very large number of low-lying states enhance the NLO properties values. These particul…

Electronic structureNonlinear opticsSeries (mathematics)Optical propertiesChemistryAb initioGeneral Physics and AstronomyNonlinear opticsElectronic structureAb initio calculations ; Electronic structure ; Nonlinear optics ; Optical materials ; Optical properties ; Organic compounds ; VB calculationsUNESCO::FÍSICA::Química físicaCoupled clusterVB calculationsAb initio quantum chemistry methodsComputational chemistryOptical materialsOrganic compoundsPhysical chemistryValence bond theorySinglet stateAb initio calculationsPhysical and Theoretical Chemistry:FÍSICA::Química física [UNESCO]
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