Hi,

Hematite has the corundum structure and it belongs to the R-3c space group (number of group is 167). It has 12 Symmetry operators (see :http://www.cryst.ehu.es/cgi-bin/cryst/programs/nph-wp-list?gnum=167&grha=rhombohedral). So you can reproduce the hexagonal shape by applying this operators.

But, there is a lot of programs can do that for you like : VESTA, Jmol ....

I send you the POSCAR of Hexagonal shape, and the CIF file

regards

Hilal

Also you can get the Wyckoff positions from your poscar with findsym and use the utilities from Bilbao Crystallographic server to build the unit cell, or just use VESTA as Hilal suggest. :-)

Mr. Manukovsky,

You need original crystallographic data.

Thank you all very much.

I'm trying to do it with VESTA, and I see a transformation matrix is required. How can I find that matrix?

Nurit.

Hi Nurit,

Here you can find more informations:

https://docs.quantumwise.com/tutorials/rhombo_hex_trigonal/rhombo_hex_trigonal.html

Hilal.

Thank you Hilal.