[Wien] How to determine the positions of atoms in cell?

[thomas.mazet]

Hello,

 There are three different crystal structures (allotropic forms) for TiO2:
Rutile (that used in Wien) SPGRP: P42/mmm Ti (0, 0, 0)  and O (0.3 0.3 0)
Anatase                    SPGRP: I41/amd Ti (0 0 0)    and O (0 0 0.26)
Brookite                   SPGRP: Pbca    Ti (0.127 0.113 0.873) 
                                   and O (0.01 0.155 0.180)  
                                   and O (0.23 0.105 0.535)
Regards
Thomas 

> Hi,professor:
>    Please tell me the general way to determine the positions of atoms in a cell.For example,in the TiO2.struct,the position of Ti is (0,0,0),and that of O is (0.3, 0.3, 0).However I look up the structure of TiO2 in the INTERNATIONAL TABLES FOR CRYSTALLOGRAPHY and know that the position of O is different with that provided by the USER GUIDE OF WIEN2K in page 138. Please help me.Thank you very much. 

-- 
Thomas MAZET
Laboratoire de Chimie du Solide Minéral (UMR 7555)
Université Henri Poincaré-Nancy I
BP 239 54506 Vandoeuvre les Nancy Cedex
FRANCE
Tel.: +33-(0)3-83-68-46-77
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