Leucite Dove M T, Cool T, Palmer D C, Putnis A, Salje E K H, Winkler B American Mineralogist 78 (1993) 486-492 On the role of Al-Si ordering in the cubic-tetragonal phase transition of leucite Sample is Order model 1 _database_code_amcsd 0001557 12.931 12.931 13.812 90 90 90 *I4_1/a 0 .25 .125 atom x y z K .3713 .3568 .1129 Si1 .0556 .3960 .1681 Al .1698 .6098 .1267 Si2 .3978 .6361 .0844 O1 .1296 .3154 .1097 O2 .0867 .5076 .1328 O3 .1429 .6857 .2281 O4 .1299 .6868 .0320 O5 .2994 .5700 .1183 O6 .4899 .6167 .1636