6533b872fe1ef96bd12d3a96
RESEARCH PRODUCT
General occurrence of polar twisted minima in the ionic singlet excited surfaces of polyenes
Jean-paul MalrieuIgnacio Nebot-gilsubject
ChemistryUNESCO::FÍSICAGeneral Physics and AstronomyIonic bondingElectronic structurePolyenesExcited StatesSelf−Consistent FieldDelocalized electronElectronic StructureAb initio quantum chemistry methods:FÍSICA [UNESCO]Polyenes ; Self−Consistent Field ; Electronic Structure ; Excited StatesExcited statePhysics::Atomic and Molecular ClustersSinglet statePhysical and Theoretical ChemistryAtomic physicsPhysics::Chemical PhysicsGround stateOpen shelldescription
Except for a few cases, the lowest closed shell SCF solutions for the twisted geometries of polyenes involves delocalized nonpolarized MO’s, and represents a meaningless mixture of radicalar gound state and ionic excited states. Higher (quasi) solutions allow a realistic approach of the polarized ionic states. Orthogonality to the radicalar ground state may be imposed without important loss of energy. Further extensive CI does not modify significantly the situation. These statements are illustrated through ab initio calculations of butadiene and hexatriene. This approach allows us to show that slight distortions stablize polar minima even in ’’homosymmetric’’ molecules such as all‐trans hexatriene twisted around the central bond. The existence of polar twisted minima in the ionic singlet excited surfaces of polyenes seems therefore a general phenomenon. Ignacio.Nebot@uv.es
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1982-09-01 |