6533b7d6fe1ef96bd1266e7c

RESEARCH PRODUCT

A comparison of density-functional-theory and coupled-cluster frequency-dependent polarizabilities and hyperpolarizabilities

Paweł SałekTrygve HelgakerD. JonssonJürgen GaussHans ÅGrenOlav Vahtras

subject

PhysicsBiophysicsHartree–Fock methodCondensed Matter PhysicsPara-nitroanilineMolecular physicsGeneralized gradientCoupled clusterQuantum mechanicsPhysics::Atomic and Molecular ClustersDensity functional theoryPhysics::Atomic PhysicsSinglet statePhysics::Chemical PhysicsPhysical and Theoretical ChemistryMolecular BiologyLinear response theoryExcitation

description

The frequency-dependent polarizabilities and hyperpolarizabilities of HF, CO, H2O and para-nitroaniline calculated by density-functional theory are compared with accurate coupled-cluster results. Whereas the local-density approximation and the generalized gradient approximation (BLYP) perform very similarly and overestimate polarizabilities and, in particular, the hyperpolarizabilities, hybrid density-functional theory (B3LYP) performs better and produces results similar to those obtained by coupled-cluster singles-and-doubles theory. Comparisons are also made for singlet excitation energies, calculated using linear response theory.

https://doi.org/10.1080/00268970412331319254