Al2O3 Ollivier B, Retoux R, Lacorre P, Massiot D, Ferey G Journal of Materials Chemistry 7 (1997) 1049-1056 Crystal structure of kappa-alumina: an X-ray powder diffraction, TEM and NMR study Note: pyroxene structure _cod_database_code 1000442 _database_code_amcsd 0013079 4.8437 8.3300 8.9547 90 90 90 Pna2_1 atom x y z Al1 .6787 .8416 0 Al2 .1846 .3432 .7868 Al3 .8115 .6489 .6972 Al4 .6677 .4696 .9993 O1 .3290 .8313 .8927 O2 .0248 .4908 .6292 O3 .4717 .6647 .6381 O4 .5145 .6728 .1212 O5 .8608 .3301 .8662 O6 .3360 .4992 .9000