Corundum Kirfel A, Eichhorn K Acta Crystallographica A46 (1990) 271-284 Accurate structure analysis with synchrotron radiation. The electron density in Al2O3 and Cu2O Locality: synthetic _database_code_amcsd 0009327 4.7570 4.7570 12.9877 90 90 120 R-3c atom x y z U(1,1) U(2,2) U(3,3) U(1,2) U(1,3) U(2,3) Al 0 0 .35218 .00259 .00259 .00276 .001295 0 0 O .30625 0 .25 .00292 .00325 .00334 .00146 .000395 .00079