Set the value of the sr parameter in the damping function of the VDW correction in the Tkatchenko-Scheffler scheme. See Equation (12) of Phys. Rev. Lett. 102 073005 (2009). This parameter depends on the xc functional used. The default value is 0.94, which holds for PBE. For PBE0, a value of 0.96 should be used.
No correction is applied.
The scheme of Tkatchenko and Scheffler, Phys. Rev. Lett. 102
The DFT-D3 scheme of S. Grimme, J. Antony, S. Ehrlich, and
S. Krieg, J. Chem. Phys. 132, 154104 (2010).
(Experimental) You can use this variable to override the parametrization used by the DFT-D3 van deer Waals correction. Normally you need not set this variable, as the proper value will be selected by Octopus (if available).
This variable takes a string value, the valid values can be found in the source file ‘external_libs/dftd3/core.f90’. For example you can use:
VDWD3Functional = ‘pbe’
If XYZVelocities, PDBVelocities, and XSFVelocities are not present, Octopus will try to fetch the initial atomic velocities from this block. If this block is not present, Octopus will set the initial velocities to zero. The format of this block can be illustrated by this example:
‘C’ | -1.7 | 0.0 | 0.0
‘O’ | 1.7 | 0.0 | 0.0
It describes one carbon and one oxygen moving at the relative velocity of 3.4 velocity units.
Note: It is important for the velocities to maintain the ordering
in which the atoms were defined in the coordinates specifications.
In the calculation of the vibrational spectrum, it is not necessary to read the velocity at every time step. This variable controls the integer factor between the simulation time step and the time step used to calculate the vibrational spectrum.
Describes a volume in space defined through the addition and substraction of spheres. The first field is always "+" (include points inside the volume) or "-" (exclude points inside the volume)
"+"/"-" | vol_sphere | center_x | center_y | center_z | radius
"+"/"-" | vol_slab | thickness