Complexity in seemingly simple sodium magnesiate systems.
Francos, J.; Fleming, B. J.; García-Álvarez, P; Kennedy, A. R.; Reilly, K.; Robertson, G. M.; Robertson, S. D.; O'Hara, C T; Dalton transactions (Cambridge, England : 2003) 43 (2014) 14424–14431; doi:10.1039/c4dt00921e

data_7031476
_publ_section_title
;
 Complexity in seemingly simple sodium magnesiate systems.
;
_journal_issue                   38
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              14424
_journal_page_last               14431
_journal_paper_doi               10.1039/c4dt00921e
_journal_volume                  43
_journal_year                    2014
_chemical_formula_sum            'C28 H77 Mg N6 Na Si4'
_chemical_formula_weight         657.62
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           33
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_atom_sites_solution_secondary   difmap
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_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   39.1203(11)
_cell_length_b                   8.7705(3)
_cell_length_c                   25.6241(7)
_cell_measurement_reflns_used    10810
_cell_measurement_temperature    123(2)
_cell_measurement_theta_max      28.7457
_cell_measurement_theta_min      3.1784
_cell_volume                     8791.7(5)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      123(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.873
_diffrn_measurement_device_type  omega-scans
_diffrn_measurement_method       'Oxford Diffraction Xcalibur E'
_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  0.0407
_diffrn_reflns_av_sigmaI/netI    0.0761
_diffrn_reflns_limit_h_max       47
_diffrn_reflns_limit_h_min       -48
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       34
_diffrn_reflns_limit_l_min       -28
_diffrn_reflns_number            32190
_diffrn_reflns_theta_full        26.00
_diffrn_reflns_theta_max         28.89
_diffrn_reflns_theta_min         3.18
_exptl_absorpt_coefficient_mu    0.183
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.90096
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.34.40 (release 27-08-2010 CrysAlis171 .NET)
(compiled Aug 27 2010,11:50:40)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    0.994
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             2928
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.365
_refine_diff_density_min         -0.444
_refine_diff_density_rms         0.059
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.01(10)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.076
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     838
_refine_ls_number_reflns         16630
_refine_ls_number_restraints     129
_refine_ls_restrained_S_all      1.075
_refine_ls_R_factor_all          0.0838
_refine_ls_R_factor_gt           0.0652
_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^)+(0.0443P)^2^+3.5036P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1235
_refine_ls_wR_factor_ref         0.1322
_reflns_number_gt                13362
_reflns_number_total             16630
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c4dt00921e2.cif
_cod_data_source_block           shelxl1
_cod_depositor_comments
'Adding full bibliography for 7031474--7031478.cif.'
_cod_original_sg_symbol_H-M      'P n a 2 1'
_cod_database_code               7031476