Isokite, CaMg(PO~4~)F~0.8~(OH)~0.2~, isomorphous with titanite
Yang, Hexiong; Zwick, Justin; Downs, Robert T.; Costin, Gelu; Acta Crystallographica Section C 63 (2007) i89–i90; doi:10.1107/S0108270107041169

data_2016185
_publ_section_title
;
 Isokite, CaMg(PO~4~)F~0.8~(OH)~0.2~, isomorphous with titanite
;
_journal_coeditor_code           FA3103
_journal_issue                   10
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              i89
_journal_page_last               i90
_journal_paper_doi               10.1107/S0108270107041169
_journal_volume                  63
_journal_year                    2007
_chemical_formula_analytical     'Ca Mg P O4.20 F0.80 H0.20'
_chemical_formula_iupac          'Ca Mg (P O4) O0.20 F0.80'
_chemical_formula_moiety         'Ca F0.80 Mg O4.20 P'
_chemical_formula_sum            'Ca F0.8 Mg O4.2 P'
_chemical_formula_weight         177.76
_chemical_name_common            Isokite
_chemical_name_systematic
;
calcium magnesium phosphate fluoride
;
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 112.246(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.5109(3)
_cell_length_b                   8.7301(5)
_cell_length_c                   6.9046(5)
_cell_measurement_reflns_used    868
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      69.621
_cell_measurement_theta_min      9.339
_cell_volume                     363.25(4)
_computing_cell_refinement       'SAINT (Bruker, 2005)'
_computing_data_collection       'APEX2 (Bruker, 2003)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    'XtalDraw (Downs & Hall-Wallace, 2003)'
_computing_publication_material  'SHELXTL (Bruker, 1997)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.994
_diffrn_measured_fraction_theta_max 0.994
_diffrn_measurement_device_type  'Bruker APEXII ? CCD area-detector'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0308
_diffrn_reflns_av_sigmaI/netI    0.0336
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            3037
_diffrn_reflns_theta_full        35.09
_diffrn_reflns_theta_max         35.09
_diffrn_reflns_theta_min         4.11
_exptl_absorpt_coefficient_mu    2.250
_exptl_absorpt_correction_T_max  0.8957
_exptl_absorpt_correction_T_min  0.8766
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 2005)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    3.250
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             352
_exptl_crystal_size_max          0.06
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.623
_refine_diff_density_min         -0.660
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.045
_refine_ls_matrix_type           full
_refine_ls_number_parameters     40
_refine_ls_number_reflns         801
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.045
_refine_ls_R_factor_all          0.0403
_refine_ls_R_factor_gt           0.0297
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0379P)^2^+0.3685P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0751
_refine_ls_wR_factor_ref         0.0805
_reflns_number_gt                660
_reflns_number_total             801
_reflns_threshold_expression     I>2\s(I)
_cod_duplicate_entry             9011393
_cod_data_source_file            fa3103.cif
_cod_data_source_block           I
_cod_original_formula_sum        'Ca F0.80 Mg O4.20 P'
_cod_database_code               2016185
_cod_database_fobs_code          2016185