Mullite Balzar D, Ledbetter H American Mineralogist 78 (1993) 1192-1196 Crystal structure and compressibility of 3:2 mullite _database_code_amcsd 0001618 7.54336 7.69176 2.88402 90 90 90 Pbam atom x y z occ Biso Al 0 0 0 .23 Al1 .1485 .3407 .5 .525 .24 Si1 .1485 .3407 .5 .342 .24 Al2 .2610 .2073 .5 .100 .00 Si2 .2610 .2073 .5 .033 .00 O1 .3577 .4235 .5 2.12 O2 .5 0 .5 .475 2.06 O3 .4635 .0465 .5 .198 4.53 O4 .1265 .2197 0 2.16