Synthesis and characterisation of a series of alkylmagnesium amide and related oxygen-contaminated "alkoxy" compounds.
Conway, Ben; Hevia, Eva; Kennedy, Alan R.; Mulvey, Robert E.; Weatherstone, Susan; Dalton transactions (Cambridge, England : 2003)  (2005) 1532–1544; doi:10.1039/b501502b

data_7008326
_publ_section_title
;
 Synthesis and characterisation of a series of alkylmagnesium amide and
 related oxygen-contaminated "alkoxy" compounds.
;
_journal_issue                   8
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              1532
_journal_page_last               1544
_journal_paper_doi               10.1039/b501502b
_journal_year                    2005
_chemical_formula_sum            'C20 H54 Mg2 N2 Si4'
_chemical_formula_weight         483.63
_chemical_name_systematic
;
?
;
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_atom_sites_solution_hydrogens   geom
_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            8
_cell_length_a                   17.0678(2)
_cell_length_b                   16.6597(2)
_cell_length_c                   21.6558(4)
_cell_measurement_reflns_used    7744
_cell_measurement_temperature    123(2)
_cell_measurement_theta_max      27.48
_cell_measurement_theta_min      1.02
_cell_volume                     6157.71(15)
_computing_data_collection       'Collect and Denzo'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    Shelxs
_diffrn_ambient_temperature      123(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Nonius Kappa CCD'
_diffrn_measurement_method       'phi and omega scans'
_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  0.1114
_diffrn_reflns_av_sigmaI/netI    0.0762
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -22
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -28
_diffrn_reflns_number            80593
_diffrn_reflns_theta_full        27.50
_diffrn_reflns_theta_max         27.50
_diffrn_reflns_theta_min         1.88
_diffrn_standards_decay_%        0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.243
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.043
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             2144
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.25
_refine_diff_density_max         0.322
_refine_diff_density_min         -0.236
_refine_diff_density_rms         0.059
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.037
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     286
_refine_ls_number_reflns         7066
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.037
_refine_ls_R_factor_all          0.1003
_refine_ls_R_factor_gt           0.0475
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0518P)^2^+0.5353P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1013
_refine_ls_wR_factor_ref         0.1158
_reflns_number_gt                4381
_reflns_number_total             7066
_reflns_threshold_expression     I>2sigma(I)
_cod_data_source_file            b501502b.txt
_cod_data_source_block           grem109
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      Pbca
_cod_database_code               7008326