TY - JOUR
T1 - An assessment of density functional methods for potential energy curves of nonbonded interactions
T2 - The XYG3 and B97-D approximations
AU - Vázquez-Mayagoitia, Álvaro
AU - Sherrill, C. David
AU - Aprà, Edoardo
AU - Sumpter, Bobby G.
PY - 2010/3/9
Y1 - 2010/3/9
N2 - A recently proposed double-hybrid functional called XYG3 and a semilocal GGA functional (B97-D) with a semiempirical correction for van der Waals interactions have been applied to study the potential energy curves along the dissociation coordinates of weakly bound pairs of molecules governed by London dispersion and induced dipole forces. Molecules treated in this work were the parallel sandwich, T-shaped, and parallel-displaced benzene dimer, (C 6H6)2; hydrogen sulfide and benzene, H 2S C6H6; methane and benzene, CH4 C6H6; the methane dimer, (CH4)2; and the pyridine dimer, (C5H5N)2. We compared the potential energy curves of these functionals with previously published benchmarks at the coupled cluster singles, doubles, and perturbative triplets [CCSD(T)] complete-basis-set limit. Both functionals, XYG3 and B97-D, exhibited very good performance, reproducing accurate energies for equilibrium distances and a smooth behavior along the dissociation coordinate. Overall, we found an agreement within a few tenths of one kcal mol-1 with the CCSD(T) results across the potential energy curves.
AB - A recently proposed double-hybrid functional called XYG3 and a semilocal GGA functional (B97-D) with a semiempirical correction for van der Waals interactions have been applied to study the potential energy curves along the dissociation coordinates of weakly bound pairs of molecules governed by London dispersion and induced dipole forces. Molecules treated in this work were the parallel sandwich, T-shaped, and parallel-displaced benzene dimer, (C 6H6)2; hydrogen sulfide and benzene, H 2S C6H6; methane and benzene, CH4 C6H6; the methane dimer, (CH4)2; and the pyridine dimer, (C5H5N)2. We compared the potential energy curves of these functionals with previously published benchmarks at the coupled cluster singles, doubles, and perturbative triplets [CCSD(T)] complete-basis-set limit. Both functionals, XYG3 and B97-D, exhibited very good performance, reproducing accurate energies for equilibrium distances and a smooth behavior along the dissociation coordinate. Overall, we found an agreement within a few tenths of one kcal mol-1 with the CCSD(T) results across the potential energy curves.
UR - http://www.scopus.com/inward/record.url?scp=77949679522&partnerID=8YFLogxK
U2 - 10.1021/ct900551z
DO - 10.1021/ct900551z
M3 - Article
AN - SCOPUS:77949679522
SN - 1549-9618
VL - 6
SP - 727
EP - 734
JO - Journal of Chemical Theory and Computation
JF - Journal of Chemical Theory and Computation
IS - 3
ER -