Quartz Levien L, Prewitt C T, Weidner D J American Mineralogist 65 (1980) 920-930 Structure and elastic properties of quartz at pressure P = 20.7 kbar _database_code_amcsd 0000790 4.8362 4.8362 5.3439 90 90 120 *P3_221 0 0 .666666667 atom x y z B(1,1) B(2,2) B(3,3) B(1,2) B(1,3) B(2,3) Si .4630 0 0 .0070 .0057 .0035 .0029 .0002 .0004 O .4111 .2795 .1095 .0148 .0108 .0076 .0075 -.0034 -.0029