Redetermination of synthetic warwickite, Mg~3~TiO~2~(BO~3~)~2~
Kawano, Tetsuya; Yamane, Hisanori; Acta Crystallographica Section E 67 (2011) i18–i19; doi:10.1107/S1600536811002157

data_2229264
_publ_section_title
;
 Redetermination of synthetic warwickite, Mg~3~TiO~2~(BO~3~)~2~
;
_journal_coeditor_code           WM2443
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              i18
_journal_page_last               i19
_journal_paper_doi               10.1107/S1600536811002157
_journal_volume                  67
_journal_year                    2011
_chemical_formula_iupac          'Mg3 Ti O2 (B O3)2'
_chemical_formula_moiety         'B2 Mg3 O8 Ti'
_chemical_formula_structural     'Mg3 Ti O2 (B O3)2'
_chemical_formula_sum            'B2 Mg3 O8 Ti'
_chemical_formula_weight         270.45
_chemical_name_systematic
;
trimagnesium titanium(IV) dioxide bis(borate)
;
_space_group_IT_number           62
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2n'
_symmetry_space_group_name_H-M   'P n m a'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   9.3013(5)
_cell_length_b                   3.10080(14)
_cell_length_c                   9.3914(6)
_cell_measurement_reflns_used    2288
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.49
_cell_measurement_theta_min      3.08
_cell_volume                     270.86(3)
_computing_cell_refinement       'PROCESS-AUTO (Rigaku/MSC, 2005)'
_computing_data_collection       'PROCESS-AUTO (Rigaku/MSC, 2005)'
_computing_data_reduction        'PROCESS-AUTO (Rigaku/MSC, 2005)'
_computing_molecular_graphics    'VESTA (Momma & Izumi, 2008)'
_computing_publication_material  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SIR2004 (Burla <i>et al.</i>, 2005)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 10.0
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Rigaku R-AXIS RAPID II'
_diffrn_measurement_method       \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  0.0177
_diffrn_reflns_av_sigmaI/netI    0.0111
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       3
_diffrn_reflns_limit_k_min       -3
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            2510
_diffrn_reflns_theta_full        27.46
_diffrn_reflns_theta_max         27.46
_diffrn_reflns_theta_min         3.08
_exptl_absorpt_coefficient_mu    1.941
_exptl_absorpt_correction_T_max  0.839224
_exptl_absorpt_correction_T_min  0.790913
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details
;
(NUMABS; Higashi, 1999)
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    3.316
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             264
_exptl_crystal_size_max          0.170
_exptl_crystal_size_mid          0.166
_exptl_crystal_size_min          0.120
_refine_diff_density_max         0.357
_refine_diff_density_min         -0.594
_refine_ls_extinction_coef       0.039(7)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 2008)'
_refine_ls_goodness_of_fit_ref   1.204
_refine_ls_matrix_type           full
_refine_ls_number_parameters     44
_refine_ls_number_reflns         364
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.204
_refine_ls_R_factor_all          0.0267
_refine_ls_R_factor_gt           0.0257
_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^)+(0.0347P)^2^+0.3981P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0695
_refine_ls_wR_factor_ref         0.0702
_reflns_number_gt                348
_reflns_number_total             364
_reflns_threshold_expression     I>2sigma(I)
_cod_data_source_file            wm2443.cif
_cod_data_source_block           I
_cod_database_code               2229264
_cod_database_fobs_code          2229264