The diene isomerization energies dataset: A difficult test for double-hybrid density functionals?
M Wykes1, A J Pérez-Jiménez2, C Adamo3
1Madrid Institute for Advanced Studies, IMDEA Nanoscience, Calle Faraday 9, Campus Cantoblanco, E-28049 Madrid, Spain.
Abstract:
We have systematically analyzed the performance of some representative double-hybrid density functionals (including PBE0-DH, PBE-QIDH, PBE0-2, XYG3, XYGJ-OS, and xDH-PBE0) for a recently introduced database of diene isomerization energies. Double-hybrid models outperform their corresponding hybrid forms (for example, PBE0-DH, PBE0-2, and PBE-QIDH are more accurate than PBE0) and the XYG3, XYGJ-OS, and xDH-PBE0 functionals perform excellently, providing root mean square deviation values within "calibration accuracy." XYGJ-OS and xDH-PBE0 also rival the best performing post-Hartree-Fock methods at a substantially lower cost.
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