Accurate static polarizabilities by density functional theory: assessment of the PBE0 model

We analyze the performances of a new density functional model (PBE0) obtain ed combining the so-called PBE generalized gradient functional with a prede fined amount of exact exchange, in evaluating molecular dipole polarizabili ties. Five molecules, namely H2O, NH3, HF, H2S and CO, have been chosen as test cases in the evaluation of dipole moments and polarizabilities. Our re sults show that the PBE0 model outperforms other current density functional s. The performance of this model has been assessed for a set of 12 small mo lecules. Here the PRE0 results are in good agreement with experimental data and close to those obtained by sophisticated (and more time-demanding) pos t-Hartree-Fock methods. Average dipole polarizabilities have also been comp uted for a set of aliphatic and aromatic hydrocarbons, including medium- an d large-size molecules, for which post-HF calculations are too expensive. ( C) 1999 Elsevier Science B.V. All rights reserved.