Crystal structure of a strontium‒tantalum and a magnesium‒niobium heterometal alkoxide: precursors for the MOCVD of ferroelectric oxides
Jones, Anthony C.; Davies, Hywel O.; Leedham, Timothy J.; Wright, Peter J.; Crosbie, Michael J.; Steiner, Alexander; Bickley, Jamie F.; O'Brien, Paul; White, Andrew J. P.; Williams, David J.; Journal of Materials Chemistry 11 (2001) 544–; doi:10.1039/b006529n

data_7204027
_publ_section_title
;
 Crystal structure of a strontium--tantalum and a magnesium--niobium
 heterometal alkoxide: precursors for the MOCVD of ferroelectric oxides
;
_journal_issue                   2
_journal_name_full               'Journal of Materials Chemistry'
_journal_page_first              544
_journal_paper_doi               10.1039/b006529n
_journal_volume                  11
_journal_year                    2001
_chemical_formula_sum            'C28 H72 Mg Nb2 O14'
_chemical_formula_weight         843.13
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                95.79(4)
_cell_angle_beta                 110.06(4)
_cell_angle_gamma                94.27(4)
_cell_formula_units_Z            1
_cell_length_a                   8.956(3)
_cell_length_b                   11.370(3)
_cell_length_c                   11.630(5)
_cell_measurement_temperature    293(2)
_cell_volume                     1099.2(7)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.925
_diffrn_measured_fraction_theta_max 0.925
_diffrn_measurement_device_type  'Stoe IPDS'
_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  0.0517
_diffrn_reflns_av_sigmaI/netI    0.0525
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            6878
_diffrn_reflns_theta_full        24.01
_diffrn_reflns_theta_max         24.01
_diffrn_reflns_theta_min         3.07
_exptl_absorpt_coefficient_mu    0.511
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.274
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             446
_exptl_crystal_size_max          0.55
_exptl_crystal_size_mid          0.45
_exptl_crystal_size_min          0.40
_refine_diff_density_max         0.855
_refine_diff_density_min         -0.744
_refine_diff_density_rms         0.070
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.053
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     323
_refine_ls_number_reflns         3199
_refine_ls_number_restraints     576
_refine_ls_restrained_S_all      1.080
_refine_ls_R_factor_all          0.0557
_refine_ls_R_factor_gt           0.0478
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0877P)^2^+0.3501P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1313
_refine_ls_wR_factor_ref         0.1366
_reflns_number_gt                2675
_reflns_number_total             3199
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b006529n.txt
_cod_data_source_block           t3
_cod_depositor_comments
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The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0877P)^2^+0.3501P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.0877P)^2^+0.3501P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        1099.2(6)
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               7204027