data_9000788
_chemical_name 'Tephroite'
loop_
_publ_author_name
'Francis C A'
'Ribbe P H'
_journal_name_full "American Mineralogist"
_journal_volume 65
_journal_year 1980
_journal_page_first 1263
_journal_page_last 1269
_publ_section_title
;
 The forsterite-tephroite series: I. Crystal structure refinements
 Te 91
 olivine
;
_chemical_formula_sum 'Mn1.83 Mg.17 Si O4'
_cell_length_a 4.879
_cell_length_b 10.589
_cell_length_c 6.234
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 322.072
_symmetry_space_group_name_H-M 'P b n m'
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  'x,y,1/2-z'
  '-x,-y,1/2+z'
  '1/2+x,1/2-y,1/2+z'
  '1/2-x,1/2+y,1/2-z'
  '1/2-x,1/2+y,z'
  '1/2+x,1/2-y,-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Mn1   0.00000   0.00000   0.00000   0.83000
Mg1   0.00000   0.00000   0.00000   0.17000
Mn2   0.98770   0.28010   0.25000   1.00000
Si   0.42650   0.09510   0.25000   1.00000
O1   0.75740   0.09140   0.25000   1.00000
O2   0.21620   0.45250   0.25000   1.00000
O3   0.28750   0.16250   0.04010   1.00000