Phenakite Tsirelson V G, Sokolova Y V, Urusov V S Geochemistry International 24 (1987) 101-110 An X-ray diffraction study of the electron-density distribution and electrostatic potential in phenakite Be2SiO4 Locality: natural crystal from unreported locality _database_code_amcsd 0020478 12.485 12.485 8.264 90 90 120 R-3 atom x y z B(1,1) B(2,2) B(3,3) B(1,2) B(1,3) B(2,3) Be1 .98290 .19422 .41568 .00079 .00078 .00140 .00025 .00010 .00002 Be2 .98397 .19423 .08424 .00078 .00094 .00127 .00048 .00000 -.00016 Si1 .98394 .19561 .75004 .00040 .00044 .00064 .00021 -.00001 .00004 O1 .12104 .20967 .74972 .00077 .00113 .00087 .00059 -.00007 -.00005 O2 .00007 .33346 .75016 .00085 .00060 .00145 .00041 -.00014 .00000 O3 .91341 .12231 .91475 .00065 .00055 .00112 .00008 .00002 -.00002 O4 .91235 .12222 .58504 .00074 .00067 .00090 .00016 -.00005 -.00008