Spinel Martignago F, Dal Negro A, Carbonin S Physics and Chemistry of Minerals 30 (2003) 401-408 How Cr3+ and Fe3+ affect Mg-Al order-disorder transformation at high temperature in natural spinels Sample: H-Cr, 3rd run, T = 700 C _database_code_amcsd 0008806 8.1569 8.1569 8.1569 90 90 90 *Fd3m .125 .125 .125 atom x y z occ Uiso AlT .125 .125 .125 .187 .0138 MgT .125 .125 .125 .813 .0138 AlM .5 .5 .5 .8235 .0127 MgM .5 .5 .5 .091 .0127 CrM .5 .5 .5 .081 .0127 MnM .5 .5 .5 .001 .0127 ZnM .5 .5 .5 .0035 .0127 O .26242 .26242 .26242 .0149