Omphacite McCormick T C American Mineralogist 71 (1986) 1434-1440 Crystal-chemical aspects of nonstoichiometric pyroxenes Sample: Vacancy model II _database_code_amcsd 0001056 9.501 8.654 5.238 90 107.23 90 C2/c atom x y z occ B(1,1) B(2,2) B(3,3) B(1,2) B(1,3) B(2,3) Fe1 0 .90540 .25 .063 .00120 .00161 .0039 0 .00053 0 Al1 0 .90540 .25 .758 .00120 .00161 .0039 0 .00053 0 Mg1 0 .90540 .25 .179 .00120 .00161 .0039 0 .00053 0 Fe2 0 .30090 .25 .019 .00313 .00204 .0056 0 -.00031 0 Ca2 0 .30090 .25 .286 .00313 .00204 .0056 0 -.00031 0 Mg2 0 .30090 .25 .026 .00313 .00204 .0056 0 -.00031 0 Na2 0 .30090 .25 .602 .0031 .00204 .0056 0 -.00031 0 Si .28947 .09297 .22831 .00094 .00137 .0030 -.00006 .00065 -.00017 O1 .11043 .0779 .1309 .00106 .0029 .0078 .00016 .0009 -.0005 O2 .3608 .2601 .3005 .00279 .00183 .0080 -.00045 .0012 -.0006 O3 .35291 .0108 .0034 .00146 .0028 .0048 .00012 .0010 -.0011