data_global
_chemical_name_mineral 'Fermorite'
loop_
_publ_author_name
'Hughes J M'
'Drexler J W'
_journal_name_full 'Neues Jahrbuch fur Mineralogie, Monatshefte'
_journal_volume 1991 
_journal_year 1991
_journal_page_first 327
_journal_page_last 336
_publ_section_title
;
 Cation substitution in the apatite tetrahedral site:
 crystal structures of type hydroxylellestadtite and type fermorite
;
_database_code_amcsd 0014858
_chemical_compound_source 'Sitipar deposit, India'
_chemical_formula_sum '(Ca4.2 Sr.8) As1.47 P1.44 O13.31 F.345 H1.31'
_cell_length_a 9.5935
_cell_length_b 9.5966
_cell_length_c 6.9754
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 119.971
_cell_volume 556.315
_exptl_crystal_density_diffrn      3.665
_symmetry_space_group_name_H-M 'P 1 1 21/m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '-x,-y,1/2+z'
  'x,y,1/2-z'
  '-x,-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
Ca1   0.33340   0.66663   0.00160   0.84000   0.01330
Sr1   0.33340   0.66663   0.00160   0.16000   0.01330
Ca2a   0.00702   0.25046   0.25000   0.84000   0.01317
Sr2a   0.00702   0.25046   0.25000   0.16000   0.01317
Ca2b   0.74963   0.75684   0.25000   0.84000   0.01279
Sr2b   0.74963   0.75684   0.25000   0.16000   0.01279
Ca2c   0.24318   0.99288   0.25000   0.84000   0.01292
Sr2c   0.24318   0.99288   0.25000   0.16000   0.01292
As5+1   0.63019   0.02816   0.25000   0.49000   0.00823
P1   0.63019   0.02816   0.25000   0.48000   0.00823
As5+2   0.97194   0.60212   0.25000   0.49000   0.00836
P2   0.97194   0.60212   0.25000   0.48000   0.00836
As5+3   0.39803   0.36981   0.25000   0.49000   0.00823
P3   0.39803   0.36981   0.25000   0.48000   0.00823
O1a   0.32610   0.48830   0.25000   1.00000   0.01988
O1b   0.51200   0.83770   0.25000   1.00000   0.02077
O1c   0.16250   0.67470   0.25000   1.00000   0.02128
O2a   0.59210   0.46710   0.25000   1.00000   0.02406
O2b   0.53290   0.12500   0.25000   1.00000   0.02330
O2c   0.87500   0.40740   0.25000   1.00000   0.02482
O3a   0.34320   0.25580   0.06670   1.00000   0.03078
O3b   0.74460   0.08790   0.06640   1.00000   0.03002
O3c  -0.08750   0.65710   0.06650   1.00000   0.03040
O-H  -0.00180  -0.00010   0.19100   0.65500   0.02913
F   0.00200   0.00000   0.25000   0.34500   0.02533