mirror of
https://github.com/QuantumPackage/qp2.git
synced 2024-12-25 13:03:28 +01:00
114 lines
3.1 KiB
Markdown
114 lines
3.1 KiB
Markdown
# Orbital localisation
|
|
To localize the MOs:
|
|
```
|
|
qp run localization
|
|
```
|
|
By default, the different orbital classes are automatically set by splitting
|
|
the orbitales in the following classes:
|
|
- Core -> Core
|
|
- Active, doubly occupied -> Inactive
|
|
- Active, singly occupied -> Active
|
|
- Active, empty -> Virtual
|
|
- Deleted -> Deleted
|
|
The orbitals will be localized among each class, excpect the deleted ones.
|
|
If you want to choose another splitting, you can set
|
|
```
|
|
qp set mo_localization auto_mo_class false
|
|
```
|
|
and define the classes with
|
|
```
|
|
qp set_mo_class -c [] -a [] -v [] -i [] -d []
|
|
```
|
|
for more information
|
|
```
|
|
qp set_mo_class -q
|
|
```
|
|
We don't care about the name of the
|
|
mo classes. The algorithm just localizes all the MOs of
|
|
a given class between them, for all the classes, except the deleted MOs.
|
|
If you are using the last option don't forget to reset the initial mo classes
|
|
after the localization.
|
|
|
|
Before the localization, a kick is done for each mo class
|
|
(except the deleted ones) to break the MOs. This is done by
|
|
doing a given rotation between the MOs.
|
|
This feature can be removed by setting:
|
|
```
|
|
qp set localization kick_in_mos false
|
|
```
|
|
and the default angle for the rotation can be changed with:
|
|
```
|
|
qp set localization angle_pre_rot 1e-3 # or something else
|
|
```
|
|
|
|
After the localization, the MOs of each class (except the deleted ones)
|
|
can be sorted between them using the diagonal elements of
|
|
the fock matrix with:
|
|
```
|
|
qp set localization sort_mos_by_e true
|
|
```
|
|
|
|
You can check the Hartree-Fock energy before/during/after the localization
|
|
by putting (only for debugging):
|
|
```
|
|
qp set localization debug_hf true
|
|
```
|
|
|
|
## Foster-Boys & Pipek-Mezey
|
|
Foster-Boys:
|
|
```
|
|
qp set localization localization_method boys
|
|
```
|
|
|
|
Pipek-Mezey:
|
|
```
|
|
qp set localization localization_method pipek
|
|
```
|
|
|
|
# Break the spatial symmetry of the MOs
|
|
This program work exactly as the localization.
|
|
To break the spatial symmetry of the MOs:
|
|
```
|
|
qp run break_spatial_sym
|
|
```
|
|
The default angle for the rotations is too big for this kind of
|
|
application, a value between 1e-3 and 1e-6 should break the spatial
|
|
symmetry with just a small change in the energy:
|
|
```
|
|
qp set localization angle_pre_rot 1e-3
|
|
```
|
|
|
|
# With or without hessian + trust region
|
|
With hessian + trust region
|
|
```
|
|
qp set localization localisation_use_hessian true
|
|
```
|
|
It uses the trust region algorithm with the diagonal of the hessian of the
|
|
localization criterion with respect to the MO rotations.
|
|
|
|
Without the hessian and the trust region
|
|
```
|
|
qp set localization localisation_use_hessian false
|
|
```
|
|
By doing so it does not require to store the hessian but the
|
|
convergence is not easy, in particular for virtual MOs.
|
|
It seems that it not possible to converge with Pipek-Mezey
|
|
localization with this approach.
|
|
|
|
# Parameters
|
|
Some other parameters are available for the localization (qp edit for more details).
|
|
|
|
# Tests
|
|
```
|
|
qp test
|
|
```
|
|
|
|
# Org files
|
|
The org files are stored in the directory org in order to avoid overwriting on user changes.
|
|
The org files can be modified, to export the change to the source code, run
|
|
```
|
|
./TANGLE_org_mode.sh
|
|
mv *.irp.f ../.
|
|
```
|
|
|