Double-hybrid density-functional theory applied to molecular crystals

Kamal Sharkas, Julien Toulouse, Lorenzo Maschio, Bartolomeo Civalleri
2014 Journal of Chemical Physics  
We test the performance of a number of two- and one-parameter double-hybrid approximations, combining semilocal exchange-correlation density functionals with periodic local second-order Møller-Plesset (LMP2) perturbation theory, for calculating lattice energies of a set of molecular crystals: urea, formamide, ammonia, and carbon dioxide. All double-hybrid methods perform better on average than the corresponding Kohn-Sham calculations with the same functionals, but generally not better than
more » ... ard LMP2. The one-parameter double-hybrid approximations based on the PBEsol density functional gives lattice energies per molecule with an accuracy of about 6 kJ/mol, which is similar to the accuracy of LMP2. This conclusion is further verified on molecular dimers and on the hydrogen cyanide crystal.
doi:10.1063/1.4890439 pmid:25084879 fatcat:wxawoimilvhd3lx45wnave23ju