A fast doubly hybrid density functional method close to chemical accuracy using a local opposite spin ansatz.

نویسندگان

  • Igor Ying Zhang
  • Xin Xu
  • Yousung Jung
  • William A Goddard
چکیده

We develop and validate the XYGJ-OS functional, based on the adiabatic connection formalism and Görling-Levy perturbation theory to second order and using the opposite-spin (OS) ansatz combined with locality of electron correlation. XYGJ-OS with local implementation scales as N(3) with an overall accuracy of 1.28 kcal/mol for thermochemistry, bond dissociation energies, reaction barrier heights, and nonbonded interactions, comparable to that of 1.06 kcal/mol for the accurate coupled-cluster based G3 method (scales as N(7)) and much better than many popular density functional theory methods: B3LYP (4.98), PBE0 (4.36), and PBE (12.10).

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عنوان ژورنال:
  • Proceedings of the National Academy of Sciences of the United States of America

دوره 108 50  شماره 

صفحات  -

تاریخ انتشار 2011