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: M-Cr, 2nd run, T = 500 C _database_code_amcsd 0008786 8.1338 8.1338 8.1338 90 90 90 *Fd3m .125 .125 .125 atom x y z occ Uiso AlT .125 .125 .125 .117 .0113 MgT .125 .125 .125 .883 .0113 AlM .5 .5 .5 .8755 .0100 MgM .5 .5 .5 .058 .0100 CrM .5 .5 .5 .0615 .0100 MnM .5 .5 .5 .001 .0100 ZnM .5 .5 .5 .0035 .0100 O .26343 .26343 .26343 .0108