title: Dual-basis analytic gradients. 1. Self-consistent field theory.
abstract: Analytic gradients of dual-basis Hartree-Fock and density functional theory energies have been derived and implemented, which provide the opportunity for capturing large basis-set gradient effects at reduced cost. Suggested pairings for gradient calculations are 6-31G/6-31G**, dual[-f,-d]/cc-pVTZ, and 6-311G*/6-311 + +G(3df,3pd). Equilibrium geometries are produced within 0.0005 A of large-basis results for the latter two pairings. Though a single, iterative SCF response equation must be solved (unlike standard SCF gradients), it may be obtained in the smaller basis set, and integral screening further reduces the cost for well-chosen subsets. Total nuclear force calculations exhibit up to 75% savings, relative to large-basis calculations.
authors.affiliation: Department of Chemistry, University of California-Berkeley, Berkeley, CA 94720, USA. ofer4@bastille.cchem.berkeley.edu
authors.forename: Ryan P
authors.initials: RP
authors.lastname: Steele
authors.forename: Yihan
authors.initials: Y
authors.lastname: Shao
authors.forename: Robert A
authors.initials: RA
authors.lastname: DiStasio
authors.forename: Martin
authors.initials: M
authors.lastname: Head-Gordon