data_global
_amcsd_formula_title 'Na2Mg6Si8O22(OH)2'
loop_
_publ_author_name
'Camara F'
'Oberti R'
'Iezzi G'
'Della Ventura G'
_journal_name_full 'Physics and Chemistry of Minerals'
_journal_volume 30 
_journal_year 2003
_journal_page_first 570
_journal_page_last 581
_publ_section_title
;
 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 = 370 C
;
_database_code_amcsd 0008835
_chemical_formula_sum 'Na1.62 Mg6.19 Si8 O24 H2'
_cell_length_a 9.737
_cell_length_b 18.049
_cell_length_c 5.303
_cell_angle_alpha 90
_cell_angle_beta 102.22
_cell_angle_gamma 90
_cell_volume 910.849
_exptl_crystal_density_diffrn      2.911
_symmetry_space_group_name_H-M 'C 1 2/m 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,z'
  '1/2+x,1/2-y,z'
  '-x,y,-z'
  '1/2-x,1/2+y,-z'
  '-x,-y,-z'
  '1/2-x,1/2-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
NaA   0.00000   0.50000   0.00000   0.31000   0.03344
NaAm   0.03400   0.50000   0.11320   0.25000   0.04066
Mg1   0.00000   0.08820   0.50000   1.00000   0.01444
Mg2   0.00000   0.18010   0.00000   1.00000   0.01735
Mg3   0.00000   0.00000   0.00000   1.00000   0.02014
Mg4   0.00000   0.26170   0.50000   0.59500   0.02989
Na4   0.00000   0.26170   0.50000   0.40500   0.02989
Si1   0.28120   0.08500   0.27560   1.00000   0.01013
Si2   0.29170   0.17070   0.78260   1.00000   0.01229
O1   0.11330   0.08620   0.20980   1.00000   0.01178
O2   0.12180   0.17220   0.71980   1.00000   0.01824
O3   0.10900   0.00000   0.70910   1.00000   0.02267
O4   0.37280   0.24670   0.78460   1.00000   0.02584
O5   0.34660   0.12630   0.05720   1.00000   0.02343
O6   0.34450   0.11930   0.55830   1.00000   0.02508
O7   0.33890   0.00000   0.27580   1.00000   0.02153
H   0.17700   0.00000   0.73300   1.00000   0.03597
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
NaA 0.02065 0.07097 0.00422 0.00000 -0.00700 0.00000
NaAm 0.03212 0.06766 0.01960 0.00000 0.00050 0.00000
Mg1 0.02248 0.01980 0.00476 0.00000 0.01024 0.00000
Mg2 0.01606 0.01485 0.02055 0.00000 0.00300 0.00000
Mg3 0.02432 0.00495 0.02817 0.00000 0.00025 0.00000
Mg4 0.02661 0.05116 0.01728 0.00000 0.01899 0.00000
Na4 0.02661 0.05116 0.01728 0.00000 0.01899 0.00000
Si1 0.01055 0.01320 0.00762 -0.00087 0.00300 0.00047
Si2 0.01698 0.01155 0.00912 -0.00261 0.00325 0.00047
O1 0.00918 0.01485 0.01388 0.00000 0.00900 -0.00047
O2 0.02386 0.01815 0.00966 -0.00435 -0.00500 -0.00237
O3 0.02615 0.00990 0.03062 0.00000 0.00550 0.00000
O4 0.03166 0.02476 0.01742 -0.01044 -0.00200 0.00284
O5 0.02569 0.03466 0.01129 -0.00087 0.00725 0.01232
O6 0.01468 0.04126 0.01946 0.00435 0.00250 -0.01374
O7 0.01422 0.01815 0.03334 0.00000 0.00650 0.00000