Weberite Knop O, Cameron T S, Jochem K Journal of Solid State Chemistry 43 (1982) 213-221 What is the true space group of weberite? Locality: Ivigtut, Greenland Sample: Imma refinement, T = 133 K _database_code_amcsd 0013478 7.050 9.979 7.297 90 90 90 *Imma 0 .25 .25 atom x y z U(1,1) U(2,2) U(3,3) U(1,2) U(1,3) U(2,3) Na1 .25 0 .5 .0111 .0119 .0443 0 -.0033 0 Na2 0 .25 .75 .0143 .0247 .0123 0 0 .0072 Mg .25 0 0 .0045 .0045 .0075 0 .0005 0 Al 0 .25 .25 .0049 .0047 .0074 0 0 .0013 F1 0 0 .8862 .0051 .0134 .0111 0 0 0 F3 0 .1644 .4713 .0120 .0105 .0094 0 0 .0002 F5 .1845 .1374 .1804 .0085 .0088 .0141 .0032 .0014 -.0038