Na2Mg6Si8O22(OH)2 Camara F, Oberti R, Iezzi G, Della Ventura G Physics and Chemistry of Minerals 30 (2003) 570-581 The P2_1/m - C2/m phase transition in synthetic amphibole Na NaMg Mg5 Si8 O22 (OH)2: thermodynamic and crystal-chemical evaluation Sample: T = ambient _database_code_amcsd 0008832 9.685 17.920 5.268 90 102.44 90 P2_1/m atom x y z occ Biso B(1,1) B(2,2) B(3,3) B(1,2) B(1,3) B(2,3) NaA .2658 .25 .0456 .81 3.83 .0063 .0044 .0414 0 .0130 0 Mg1 -.2500 .3382 .4847 .64 .0023 .0005 .0048 0 .0008 -.0001 Mg2 -.2501 .4295 .9838 .65 .0021 .0004 .0063 0 .0010 .0002 Mg3 -.2496 .25 .9858 .61 .0021 .0004 .0050 0 .0004 0 Mg4 -.2468 .5065 .4812 .595 .80 .0024 .0007 .0072 0 .0027 .0002 Na4' -.2606 .5209 .4797 .405 1.46 Si1A .0324 .3355 .2616 .50 .0017 .0004 .0043 -.0001 .0005 -.0001 Si1B .5320 .8344 .2951 .49 .0017 .0004 .0037 0 .0006 .0001 Si2A .0407 .4215 .7678 .52 .0017 .0004 .0041 -.0001 .0005 -.0001 Si2B .5441 .9195 .7991 .60 .0020 .0005 .0046 -.0003 .0004 .0002 O1A -.1368 .3365 .1970 .59 .0019 .0005 .0048 -.0001 .0007 -.0002 O1B .3629 .8367 .2257 .58 .0018 .0005 .0046 0 .0006 0 O2A -.1300 .4215 .7021 .72 .0018 .0007 .0062 -.0001 .0010 -.0005 O2B .3735 .9219 .7355 .77 .0025 .0007 .0050 -.0001 .0008 -.0003 O3A -.1398 .25 .6937 .68 .0022 .0005 .0058 0 .0007 0 O3B .3576 .75 .7219 .71 .0017 .0006 .0071 0 .0009 0 O4A .1199 .4990 .7951 1.08 .0042 .0005 .0093 -.0006 -.0007 -.0002 O4B .6260 .9938 .7662 1.86 .0066 .0011 .0127 -.0017 -.0039 .0018 O5A .0965 .3676 .0237 .95 .0024 .0010 .0074 .0001 .0013 .0012 O5B .6000 .8852 .0970 .90 .0023 .0008 .0076 -.0002 .0009 .0009 O6A .0996 .3802 .5269 1.00 .0023 .0010 .0082 .0003 0 -.0017 O6B .5928 .8578 .5969 1.01 .0023 .0012 .0059 .0002 .0003 -.0011 O7A .0922 .25 .3006 .86 .0024 .0004 .0116 0 .0012 0 O7B .5896 .75 .2607 .87 .0021 .0004 .0136 0 .0019 0 H1 -.056 .25 .727 3.86 H2 .561 .25 .246 2.21