Predicting C-H/pi interactions with nonlocal density functional theory.
We examine the performance of a recently developed nonlocal density functional in predicting a model noncovalent interaction, namely the weak bond between an aromatic pi system and an aliphatic C--H group. The new functional is a significant improvement over traditional density functionals, providing results which compare favorably to high-level quantum-chemistry techniques, but at considerably lower computational cost. Interaction energies in several model C--H/pi systems are in good general agreement with coupled-cluster calculations, though equilibrium distances are consistently overpredicted when using the revPBE functional for exchange. The new functional predicts changes in energy upon addition of halogen substituents correctly.
Hooper
Joe
J
Naval Surface Warfare Center, Indian Head, Maryland 20640, USA. joseph.p.hooper@navy.mil
Cooper
Valentino R
VR
Thonhauser
Timo
T
Romero
Nichols A
NA
Zerilli
Frank
F
Langreth
David C
DC