data_9001779
_chemical_name 'Tremolite'
loop_
_publ_author_name
'Yang H'
'Evans B W'
_journal_name_full "American Mineralogist"
_journal_volume 81
_journal_year 1996
_journal_page_first 1117
_journal_page_last 1125
_publ_section_title
;
 X-ray structure refinements of tremolite at 140 and 295 K: Crystal chemistry an
 petrologic implications
 T = 140 K
;
_chemical_formula_sum 'Mg5 Ca2 Si8 O24 H2'
_cell_length_a 9.8293
_cell_length_b 18.0307
_cell_length_c 5.2752
_cell_angle_alpha 90
_cell_angle_beta 104.846
_cell_angle_gamma 90
_cell_volume 903.710
_symmetry_space_group_name_H-M 'C 1 2/m 1'
loop_
_symmetry_equiv_pos_as_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_Uiso_or_equiv
Mg1   0.00000   0.08775   0.50000   1.00000 ?
Mg2   0.00000   0.17639   0.00000   1.00000 ?
Mg3   0.00000   0.00000   0.00000   1.00000 ?
Ca4   0.00000   0.27822   0.50000   0.50000 ?
Ca4*   0.00000   0.25882   0.50000   0.50000   0.02153
Si1   0.28039   0.08416   0.29742   1.00000 ?
Si2   0.28824   0.17133   0.80493   1.00000 ?
O1   0.11179   0.08596   0.21767   1.00000 ?
O2   0.11860   0.17124   0.72418   1.00000 ?
O3   0.11027   0.00000   0.71599   1.00000 ?
O4   0.36514   0.24820   0.79245   1.00000 ?
O5   0.34644   0.13458   0.10096   1.00000 ?
O6   0.34384   0.11833   0.59009   1.00000 ?
O7   0.33726   0.00000   0.29140   1.00000 ?
H   0.20705   0.00000   0.77993   1.00000   0.02913