Psi4 Project Logo

Interface to DKH by A. Wolf, M. Reiher, and B. A. Hess

Code author: Justin M. Turney

Section author: Justin M. Turney

Module: DKH

Input

For all electron calculations one can use the Douglas-Kroll-Hess (DKH) Hamiltonian to take into account scalar relativistic effects.

Minimal input for DKH single-point computation looks like this:

molecule {
Mg
}

set basis aug-cc-pvdz-dk
set relativistic dkh

energy('scf')

By default a 2nd-order DKH calculation is performed. To change the default order use the DKH_ORDER option. The version of the code found in Psi4 is capable of up to 4th-order DKH calculations.

Keywords

RELATIVISTIC

Relativistic Hamiltonian type

  • Type: string
  • Possible Values: NO, X2C
  • Default: NO

DKH_ORDER

Order of Douglas-Kroll-Hess

  • Type: integer
  • Default: 2

Reference

When using this code please make reference to the appropriate following paper:

  • “The Generalized Douglas-Kroll Transformation,” A. Wolf, M. Reiher, and B. A. Hess, J. Chem. Phys. 117, 9215 (2002). (doi: 10.1063/1.1515314)