Atomic Orbitals

AOLoewdin
Section: Atomic Orbitals
Type: logical
Default: no

This option determines if the atomic orbital basis is orthogonalized or not. This is done for using the Loewdin orthogonalization scheme. The default is set to no for the moment as this option is not yet implemented for isolated systems, and seems to lead to important egg-box effect


AONormalize
Section: Atomic Orbitals
Type: logical
Default: yes

If set to yes, Octopus will normalize the atomic orbitals individually. This variable is ignored is AOLoewdin is set to yes.


AOSubmesh
Section: Atomic Orbitals
Type: logical

If set to yes, Octopus will use submeshes to internally store the orbitals with their phase instead of storing them on the mesh. This is usually slower for small periodic systems, but becomes advantageous for large supercells. Submeshes are not compatible with Loewdin orthogonalization. For periodic systems, the default is set to no, whereas it is set to yes for isolated systems.


AOThreshold
Section: Atomic Orbitals
Type: float
Default: 0.01

Determines the threshold used to compute the radius of the atomic orbitals for DFT+U and for Wannier90. This radius is computed by making sure that the absolute value of the radial part of the atomic orbital is below the specified threshold. This value should be converged to be sure that results do not depend on this value. However increasing this value increases the number of grid points covered by the orbitals and directly affect performances.


AOTruncation
Section: Atomic Orbitals
Type: flag
Default: ao_full

This option determines how Octopus will truncate the orbitals used for DFT+U. Except for the full method, the other options are only there to get a quick idea.
Options: