Merwinite
Moore P B, Araki T
American Mineralogist 57 (1972) 1355-1374
Atomic arrangement of merwinite, Ca3Mg[SiO4]2, an unusual dense-packed
structure of geophysical interest
_database_code_amcsd 0000294
13.254 5.293 9.328 90 91.90 90 P2_1/a
atom     x      y      z Biso
Ca1  .2563  .1789  .2234  .70
Ca2  .0811  .2271 -.0753  .66
Ca3  .0978  .7333  .4254  .73
Mg   .0043  .2566  .2535  .42
Si1  .1326  .2293  .6008  .19
Si2  .1412  .7280  .0931  .18
O1   .0740  .2123  .4450 1.04
O2   .0632  .4193  .6937  .96
O3   .1253 -.0475  .6773  .76
O4   .2414  .3618  .5940  .91
O5   .0768  .7064 -.0591  .87
O6   .2548  .8130  .0683  .82
O7   .1266  .4726  .1853  .74
O8   .0832 -.0424  .1751  .84