Cummingtonite Yang H, Smyth J R American Mineralogist 81 (1996) 363-368 Crystal structure of a P2_1/m ferromagnesian cummingtonite at 140 K T = 140 K _database_code_amcsd 0001788 9.492 18.093 5.292 90 102.11 90 P2_1/m atom x y z occ B(1,1) B(2,2) B(3,3) B(1,2) B(1,3) B(2,3) Mg1 -.2496 .3369 .4888 .800 .0013 .0002 .0022 -.0001 .0005 .0001 Fe1 -.2496 .3369 .4888 .200 .0013 .0002 .0022 -.0001 .0005 .0001 Mg2 -.2503 .4270 .9886 .911 .0014 .0003 .0022 -.0001 .0002 .0000 Fe2 -.2503 .4270 .9886 .089 .0014 .0003 .0022 -.0001 .0002 .0000 Mg3 -.2491 .25 .9905 .831 .0013 .0003 .0024 0 .0002 0 Fe3 -.2491 .25 .9905 .169 .0013 .0003 .0024 0 .0002 0 Mg4 -.2522 .5094 .4848 .094 .0014 .0004 .0015 .0000 .0006 .0000 Fe4 -.2522 .5094 .4848 .906 .0014 .0004 .0015 .0000 .0006 .0000 Si1a .0385 .3346 .2626 .0008 .0002 .0020 .0000 -.0001 .0000 Si1b .5378 .8335 .2874 .0014 .0002 .0017 -.0001 .0004 .0000 Si2a .0460 .4200 .7688 .0013 .0002 .0021 -.0001 .0001 .0000 Si2b .5494 .9175 .7937 .0008 .0003 .0015 -.0001 -.0003 .0001 O1a -.1352 .3368 .1992 .0008 .0004 .0019 .0000 .0002 -.0002 O1b .3647 .8374 .2194 .0019 .0001 .0044 .0001 .0005 .0004 O2a -.1280 .4222 .7057 .0014 .0003 .0047 -.0002 .0010 .0000 O2b .3750 .9223 .7316 .0009 .0003 .0043 .0001 .0002 .0004 O3a -.1336 .25 .6986 .0024 .0004 .0035 0 .0010 0 O3b .3613 .75 .7171 .0015 .0002 .0036 0 .0001 0 O4a .1280 .4977 .7811 .0010 .0002 .0047 -.0002 -.0005 .0003 O4b .6329 .9929 .7613 .0025 .0006 .0037 -.0003 .0009 -.0004 O5a .1010 .3733 .0341 .0013 .0005 .0036 -.0001 .0003 .0010 O5b .6032 .8871 .0905 .0016 .0003 .0025 .0001 .0001 .0002 O6a .1035 .3783 .5313 .0015 .0006 .0039 .0002 -.0005 -.0004 O6b .5974 .8605 .5827 .0011 .0006 .0029 .0002 -.0002 -.0003 O7a .0948 .25 .2917 .0021 .0005 .0032 0 -.0002 0 O7b .5925 .75 .2579 .0012 .0002 .0058 0 .0016 0