LOCPROJ: Difference between revisions

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:The radial specifiers may be modified using (optional) modification statements:
:The radial specifiers may be modified using (optional) modification statements:
::'''Pr''' [ ''n<sup>th</sup>-of-l''  [ ''species-number'' ] ]
::'''Pr''' [ ''n<sup>th</sup>-of-l''  [ ''species-number'' ] ]
::: ''n<sup>th</sup>-of-l'': tells the code to use the radial function of the ''n<sup>th</sup>'' projector with the angular moment specified in the ''<functions-Ylm-specs>'' part. By default, the projector that corresponds to the highest bound state of the relevant angular moment will be used.
::: ''n<sup>th</sup>-of-l'': tells the code to use the radial function of the ''n<sup>th</sup>'' projector with the angular moment specified in the ''<functions-Ylm-specs>'' part. The local basis of our PAW datasets typically contains 2 channels (projectors) per angular moment. By default, the projector that corresponds to the highest bound state of the relevant angular moment will be used.


::: ''species-number'': is a modifier that may be used to specify from which PAW dataset in the current {{FILE|POTCAR}} file the radial functions should be derived. When the positions of the local functions are specified by means of the ionic site indices of the {{FILE|POSCAR}} file, the code will default to the corresponding atomic types.   
::: ''species-number'': is a modifier that may be used to specify from which PAW dataset in the current {{FILE|POTCAR}} file the radial functions should be derived. When the positions of the local functions are specified by means of the ionic site indices of the {{FILE|POSCAR}} file, the code will default to the corresponding atomic types.   
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::'''Ps''' [ ''n<sup>th</sup>-of-l''  [ ''species-number'' ] ]
::'''Ps''' [ ''n<sup>th</sup>-of-l''  [ ''species-number'' ] ]
::: ''n<sup>th</sup>-of-l'': tells the code to use the radial function of the ''n<sup>th</sup>'' pseudo partial wave with the angular moment specified in the ''<functions-Ylm-specs>'' part. By default, the projector that corresponds to the highest bound state of the relevant angular moment will be used.
::: ''n<sup>th</sup>-of-l'': tells the code to use the radial function of the ''n<sup>th</sup>'' pseudo partial wave with the angular moment specified in the ''<functions-Ylm-specs>'' part. The local basis of our PAW datasets typically contains 2 channels (pseudo partial waves) per angular moment. By default, the pseudo partial wave that corresponds to the highest bound state of the relevant angular moment will be used.


::: ''species-number'': is a modifier that may be used to specify from which PAW dataset in the current {{FILE|POTCAR}} file the radial functions should be derived. When the positions of the local functions are specified by means of the ionic site indices of the {{FILE|POSCAR}} file, the code will default to the corresponding atomic types.   
::: ''species-number'': is a modifier that may be used to specify from which PAW dataset in the current {{FILE|POTCAR}} file the radial functions should be derived. When the positions of the local functions are specified by means of the ionic site indices of the {{FILE|POSCAR}} file, the code will default to the corresponding atomic types.   

Revision as of 19:03, 10 January 2017

LOCPROJ = <sites> : <functions-Ylm-specs> : <functions-radial-specs>
Default: LOCPROJ = None 

Description: by means of the LOCPROJ-tag one may specify a (set of) local function(s) on which the orbitals are to be projected. These projections are written to the PROJCAR, LOCPROJ, and vasprun.xml files.


A valid LOCPROJ specification consists of three parts separated by colons (":"), above denoted as <sites>, <functions-Ylm-specs>, and <functions-radial-specs>. These parts define the sites on which the local functions are centered, specify their angular character, and their radial behaviour, respectively.

  • <sites>
The sites on which the local functions are centered may be specified in two ways. One can use the index of the ionic positions as defined in the POSCAR file. For instance:
1 2 6-8
will select sites 1,2,6,7, and 8, as defined in the POSCAR file.
Alternatively one may specify a position in terms of direct coordinates of the real space lattice, for instance as:
(0.5, 0, 0)
These modes of specification may be mixed as well, for instance as:
1 (0.5, 0, 0) 8 
  • <functions-Ylm-specs>
The angular character of the local functions on the specified sites. Valid specifications are:
s
p py pz px
d dxy dyz dz2 dxz dx2-y2
f fy(3x2-y2) fxyz fyz2 fz3 fxz2 fz(x2-y2) fx(x2-3y2)
sp sp-1 sp-2
sp2 sp2-1 sp2-2 sp2-3
sp3 sp3-1 sp3-2 sp3-3 sp3-4
sp3d sp3d-1 sp3d-2 sp3d-3 sp3d-4 sp3d-5
sp3d2 sp3d2-1 sp3d2-2 sp3d2-3 sp3d2-4 sp3d2-5 sp3d2-6
The definition of the sp, sp2, sp3, sp3d, and sp3d2 hybrid functions is consistent with the definition used by WANNIER90 (see section 3.4 of the WANNIER90 manual).
These specifiers may be combined as well:
p sp-1 dxy
which is means: "put p functions (≡ px, py, and pz), a sp-1 function, and a dxy function on all sites specified in the <sites> part.
  • <functions-radial-specs>
The radial part of the local functions may be of one of the three following types:
Pr: use the PAW projectors
Ps: use the PAW pseudo partial waves
Hy: use hydrogen-like (Slater type) functions (see section 3.4 of the WANNIER90 manual)
Caveat: when using radial functions derived from the PAW datasets, i.e., of type Pr or Ps, one can only specify pure spherical harmonics with the same angular moment l in the <functions-Ylm-specs> part. This means, s, p, d, f, and/or their respective separate constituents.
The radial specifiers may be modified using (optional) modification statements:
Pr [ nth-of-l [ species-number ] ]
nth-of-l: tells the code to use the radial function of the nth projector with the angular moment specified in the <functions-Ylm-specs> part. The local basis of our PAW datasets typically contains 2 channels (projectors) per angular moment. By default, the projector that corresponds to the highest bound state of the relevant angular moment will be used.
species-number: is a modifier that may be used to specify from which PAW dataset in the current POTCAR file the radial functions should be derived. When the positions of the local functions are specified by means of the ionic site indices of the POSCAR file, the code will default to the corresponding atomic types.


Ps [ nth-of-l [ species-number ] ]
nth-of-l: tells the code to use the radial function of the nth pseudo partial wave with the angular moment specified in the <functions-Ylm-specs> part. The local basis of our PAW datasets typically contains 2 channels (pseudo partial waves) per angular moment. By default, the pseudo partial wave that corresponds to the highest bound state of the relevant angular moment will be used.
species-number: is a modifier that may be used to specify from which PAW dataset in the current POTCAR file the radial functions should be derived. When the positions of the local functions are specified by means of the ionic site indices of the POSCAR file, the code will default to the corresponding atomic types.


Hy [ n [ Zα ] ]
  • Examples
Combining the above, we might specify:
LOCPROJ = 1 : s : Hy
to put a hydrogenic 1s function on the first ionic position specified in the POSCAR file.


The LOCPROJ file

Related Tags and Sections

LORBIT