[Wien] Symmetry related

[Víctor Luaña Cabal]

On Sat, May 02, 2015 at 08:25:25AM +0000, Lawal Mohammed wrote:
> Dear Developers and Users
>  Please what is wrong in having P1 symmetry? I got P1 when I
> initialized supercell calculations. In the mail archive P1 is regarded
> as less efficient. How can I improve the symmetry at the same time
> maintaining same structure? Could somebody elaborate please.

Lawal,

1) Nothing is wrong. P1 eans that there is no rotational symmetry
   available in your crystal. Rotattion, reflection, inversion, etc.

2) Unfortunately symmetry elements (other than traslation) are used
   by the codes to refuce the computationl cost so it may represent
   bad news. Traslation is also used, but that is implicit, as
   you are using solid state codes designed for crystals.

3) This computer experiment may help you to understand: Take a simple
   compund and reduce the symetry progressively. You will see how the
   computer time required for the calculation increases. The less
   symmetry operations available the higher the cpu involved.
   Bad news if your disponibility of computer resources is limited.

Best regards,
             Dr. Víctor Luaña
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! Dr.Víctor Luaña, in silico chemist & prof. ! 
! Departamento de Química Física y Analítica ! 
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