Weak Interactions NWCHEM

DFT Semi-empirical Dispersion (DFT-D)

I implemented (D2), and interfaced with the original code (D3),** the Grimme's approaches empirical energy dispersion contribution to exchange-correlation potentials to DFT.

The code allows to compute energy, gradients and hessians (vibrational analysis) with empirical dispersion.

If you use any of the Grimme's methods together NWChem, PLEASE cite the method used properly.

DFT-D2

S. Grimme J. Comp. Chem. 27, 1787 (2006) DOI: 10.1002/jcc.20495

DFT-D3,

Stefan Grimme, Jens Antony, Stephan Ehrlich, and Helge Krieg J. Chem. Phys. 132, 154104 (2010); DOI:10.1063/1.3382344

DFT-D4 (Becke-Johnson damping)

Stefan Grimme, Stephan Ehrlich and Lars Goerigk J. Comput. Chem. 32, 1456 (2011); DOI:10.1002/jcc.21759

**Original code can be downloaded from http://toc.uni-muenster.de/DFTD3/

Input options:

set dft:vdwalpha <double>

set dft:vdwtz <boolean>

set dft:vdws6 < boolean>

set dft:vdwsr6 <double>

set dft:vdws8 <double>

set dft:vdwsr8 <double>

set dft:ivdw <integer> where:

0 is OFF

1 is for Wu-Yang

2 is for Grimme's D2

3 is for Grimme's D3

4 is for Grimme's D4 (or D3-BJ)