title: Error accumulations in adhesive energies of dihydrogen molecular chains: performances of the XYG3 type of doubly hybrid density functionals.
abstract: We have systematically analyzed the error accumulations in the adhesive energies for a series of hydrogen molecular chains calculated by various kinds of density functional theory (DFT) methods. In particular, we have focused on some representative doubly hybrid (DH) functionals of either the B2PLYP type (B2PLYP, B2PLYP-D, and B2GP-PLYP) or the XYG3 type (XYG3, XYGJ-OS, and xDH-PBE0). The hydrogen molecular chain models have recently been proposed by Zheng et al. (J. Chem. Phys. 2012, 137, 214106) to identify the delocalization errors (DEs) in thermodynamic properties. From the perspective of DEs, it is shown here that the XYG3 type of DH functionals yield good performance on the calculated adhesive energies due to the minimizing effects of DEs, highlighting the underlying physics for the successes or failures of the approximate functionals. Examination was also extended to HF-DFT, where DFT energies are evaluated with the Hartree-Fock (HF) densities.
authors.affiliation: Collaborative Innovation Center of Chemistry for Energy Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, MOE Laboratory for Computational Physical Science, Department of Chemistry, Fudan University , Shanghai 200433, China.
authors.forename: Neil Qiang
authors.initials: NQ
authors.lastname: Su
authors.forename: Xin
authors.initials: X
authors.lastname: Xu