[Wien] How to construct struct file of supercell withR type lattice

[Peter Blaha]

> I deal with R type lattice (S.G. No.167 R-3c), and
> I want to build struct file of supercell. But the 
> program (x supercell) does not support R type lattice.
> I wonder if somebody could tell me how to construct it.

Usually one wants a supercell with similar dimensions in all three directions
of space. For the rhombohedral lattice, however, a simple multiplication
of the basis vectors produces a very long unit cell, normally not what
you want.

Thus for R lattices I would recommend to convert it to the hexagonal setting
(this is already a supercell 3 times as large as the R settings) and
then go on from this structure.

For the conversion you may need to consult the Int.Tables of Crystallography
and so far you have to make this by hand. 

                                      P.Blaha
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Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
Phone: +43-1-58801-15671             FAX: +43-1-58801-15698
Email: blaha at theochem.tuwien.ac.at    WWW: http://info.tuwien.ac.at/theochem/
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