Understanding Crystal Structures: How to Read Table Data for Modeling in VESTA

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The discussion centers on understanding the structural data of a compound presented in a table format, specifically focusing on the unit cell dimensions, atomic positions, and certain columns labeled SOF and H. The unit cell is cubic with a volume of 209.58 and a space group of P a -3, indicating a specific symmetry. The user is particularly interested in the SOF column, which is interpreted as the site occupancy fraction, suggesting that the As and Se atoms occupy the same site in a disordered manner, potentially alternating or randomly distributed. The user seeks guidance on how to input this data into the VESTA modeling program, emphasizing the need for clarity on the arrangement of the As and Se atoms.
dipole
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Hello, I have a table here which describes the structure of a certain compound, but I'm unsure how exactly to read it.

Unit Cell 5.940(3) 5.940(3) 5.940(3) 90.0 90.0 90.0
Vol 209.58
Z 4
Space Group P a -3
SG Number 205
Cryst Sys cubic
Pearson cP12
Wyckoff c a
Red Cell P 5.94 5.94 5.94 90 90 90 209.585
Atom # OX SITE x y z SOF H
As 1 -1 8 c 0.383 0.383 0.383 .5 0
Se 1 -1 8 c 0.383 0.383 0.383 .5 0
Ir 1 +2 4 a 0 0 0 1. 0

I am unsure what the columns SOF and H might mean. I want to model this crystal in a program, but as you can see the As and Se atom are located in the same position, so my guess is that they somehow alternate with each other, but I'm exactly sure how to put the data in the program. I'm using VESTA if anyone's familiar with it.

Any help would be appreciated. Thanks.
 
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My best guess is SOF = site occupancy fraction. So, half of those sites are Se, and half are As. It may be disordered, so the Se and As are randomly distributed in the crystal.
 

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