Performance of a new hybrid Hartree-Fock/Kohn-Sham model (B98) in predicting vibrational frequencies, polarisabilities and NMR chemical shifts

We have implemented a new hybrid Hartree-Fock/Kohn-Sham model recently introduced by Becke (B98) in a fully self-consistent approach including analytical first and second derivatives with respect to both geometric and electromagnetic field parameters. Since this functional was originally optimized with respect to formation enthalpies only, we analyze in this Letter its performance for other properties including geometric structures, vibrational frequencies, polarisabilities and NMR chemical shifts. The results delivered by the B98 model are comparable to those of the best current functionals, namely B3LYP far geometries and vibrational frequencies and PBE0 for electric and magnetic properties. The implementation in a package including refined linear scaling approaches paves the route for more reliable studies of large systems. (C) 1999 Elsevier Science B.V. All rights reserved.