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RESEARCH PRODUCT
The à 1Au state and the T2 potential surface of acetylene: Implications for triplet perturbations in the fluorescence spectra of the à state
Yukio YamaguchiJohn F. StantonGeorge VacekGeorge VacekJürgen GaussJürgen GaussHenry F. SchaeferC. David SherrillC. David Sherrillsubject
Angular momentumZeeman effectChemistryAb initioGeneral Physics and AstronomyElectronic structureQuantum chemistryPotential energyDipolesymbols.namesakechemistry.chemical_compoundAcetylenePhysics::Atomic and Molecular ClusterssymbolsPhysics::Chemical PhysicsPhysical and Theoretical ChemistryAtomic physicsdescription
The cis–trans isomerization reaction on the T2 surface of acetylene and the lowest excited singlet state of acetylene, A 1Au, are investigated by ab initio electronic structure theory. We report optimized geometries, dipole moments, and harmonic vibrational frequencies of stationary points and adiabatic energy differences between them using basis sets as large as triple‐ζ plus double polarization with higher angular momentum functions, TZ(2df,2pd), and theoretical methods up to coupled‐cluster singles and doubles with a perturbative triples correction [CCSD(T)] and the equation‐of‐motion coupled‐cluster method (EOM‐CCSD). Our theoretical predictions should aid the interpretation of observations from a series of recent spectroscopic studies involving excited electronic states of acetylene. In particular, the present theoretical results rule out several possible explanations for the anomalous sudden increase in detectable Zeeman anticrossings reported by Dupre et al. [Chem. Phys. 152, 293 (1991)].
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1996-06-01 | The Journal of Chemical Physics |