A Novel Group of Alkaline Earth Metal Amides: Syntheses and Characterization of M[N(2,6-iPr2C6H3)(SiMe3)]2(THF)2 (M = Mg, Ca, Sr, Ba) and the Linear, Two-Coordinate Mg[N(2,6-iPr2C6H3)(SiMe3)]2
Wilda Vargas; Ulrich Englich; Karin Ruhlandt-Senge; Inorganic Chemistry 41 (2002) 5602–5608; doi:10.1021/ic0203668

data_4318682
_publ_section_title
;
 A Novel Group of Alkaline Earth Metal Amides: Syntheses and
 Characterization of M[N(2,6-iPr2C6H3)(SiMe3)]2(THF)2 (M = Mg, Ca, Sr, Ba)
 and the Linear, Two-Coordinate Mg[N(2,6-iPr2C6H3)(SiMe3)]2
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              5602
_journal_page_last               5608
_journal_paper_doi               10.1021/ic0203668
_journal_volume                  41
_journal_year                    2002
_chemical_formula_sum            'C38 H68 Ba N2 O2 Si2'
_chemical_formula_weight         778.46
_space_group_IT_number           13
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yac'
_symmetry_space_group_name_H-M   'P 1 2/n 1'
_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                 101.67
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   20.5476(2)
_cell_length_b                   10.0353(2)
_cell_length_c                   20.9020(4)
_cell_measurement_temperature    293(2)
_cell_volume                     4220.93(12)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.932
_diffrn_measured_fraction_theta_max 0.932
_diffrn_measurement_device_type  'CCD Area Detector'
_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  0.0406
_diffrn_reflns_av_sigmaI/netI    0.0542
_diffrn_reflns_limit_h_max       27
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            25994
_diffrn_reflns_theta_full        28.30
_diffrn_reflns_theta_max         28.30
_diffrn_reflns_theta_min         1.27
_diffrn_standards_decay_%        none
_exptl_absorpt_coefficient_mu    1.029
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'R. Blessing, Acta Cryst. (1995) A51 33-38.'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.225
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plates
_exptl_crystal_F_000             1640
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.929
_refine_diff_density_min         -0.381
_refine_diff_density_rms         0.084
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.041
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     407
_refine_ls_number_reflns         9800
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.041
_refine_ls_R_factor_all          0.0573
_refine_ls_R_factor_gt           0.0363
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0265P)^2^+0.8174P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0669
_refine_ls_wR_factor_ref         0.0722
_reflns_number_gt                7711
_reflns_number_total             9800
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic0203668_5.cif
_cod_data_source_block           sad
_cod_original_cell_volume        4220.97(12)
_cod_database_code               4318682