Example: Density-Dependent Dispersion Correction (dDsC): CH4-dimer

Download methane_dimer_dispersion.run

The density-dependent dispersion energy correction, dDsC, by S.N. Steinmann and C. Corminboeuf, is used to calculate interactions between non-overlapping densities, which standard density functional approximations cannot accurately describe. The example is for the methane dimer.

The ‘debug dispersion’ is included such that in the output one can find more details on the exact parameters that are used.

$ADFBIN/adf << eor
TITLE methane-dimer non-relativistic

debug dispersion

ATOMS
C  -0.000959    0.000775    1.853082
H  -0.747186    0.712608    1.489389
H   0.987865    0.294742    1.490258
H  -0.241511   -0.998876    1.480724
H  -0.002970   -0.005330    2.946903
C   0.000962   -0.000776   -1.853082
H   0.004264    0.004684   -2.946903
H  -0.989749   -0.289559   -1.491241
H   0.743184   -0.716138   -1.488107
H   0.246099    0.997870   -1.481022
End

Basis
 Type TZP
End

addDiffusefit
NumericalQuality good

XC
 GGA Becke LYP
 Dispersion DDsC
End

Geometry
End

eprint
geostep Energy GradientTerms Gradients Upd
end

symmetry nosym

End input
eor