Example: Graphene sheet with dispersion correction

Download Graphene_Dispersion.run

A normal GGA would give no interaction between two graphene sheets.

Use the dispersion option in the XC keyblock.

In the first run we use BP86-D, and in the second BLYP-D3.

$ADFBIN/band << eor
TITLE Dispersion energy with two parallel graphene sheets

kspace 3
accuracy 4.5

XC
gga scf bp86
dispersion default
end

dependency basis=1e-6

UNITS
    length Angstrom
    angle Degree
END

ATOMS
   C    0.00  0.0000000000  0.000
   C    0.00  0.0000000000 -3.355
   C    1.23  0.7101408312  0.000
   C   -1.23 -0.7101408311 -3.355
END

Lattice
   2.46 0.000000000 0.00
   1.23 2.130422493 0.00
End

CONVERGENCE
CRITERION 1.0e-4
Degenerate default
END

DIIS
CLARGE 10
CHUGE 30
DIMIX 0.3
NVCTRX 10
NCYCLEDAMP 5
END

SCF
iterations 50
mixing 0.2
END

BasisDefaults
BasisType TZP
Core Large
End
end input
eor

rm RUNKF

$ADFBIN/band << eor
TITLE Grimme3 dispersion energy with two parallel graphene sheets

kspace 3
accuracy 4.5

XC
gga scf blyp
dispersion Grimme3
end

dependency basis=1e-6

Gradients
End

UNITS
    length Angstrom
    angle Degree
END

ATOMS
   C    0.00  0.0000000000  0.000
   C    0.00  0.0000000000 -3.355
   C    1.23  0.7101408312  0.000
   C   -1.23 -0.7101408311 -3.355
END

Lattice
   2.46 0.000000000 0.00
   1.23 2.130422493 0.00
End

CONVERGENCE
CRITERION 1.0e-4
Degenerate default
END

DIIS
CLARGE 10
CHUGE 30
DIMIX 0.3
NVCTRX 10
NCYCLEDAMP 5
END

SCF
iterations 50
mixing 0.2
END

BasisDefaults
BasisType TZP
Core Large
End

end input
eor