Homoleptic tris(methoxydimethylsilyl)silanides of the alkaline earth metals: first zwitterionic silanides with two naked silyl anions
Bryan Carlson; Adelia J. A. Aquino; Louisa J. Hope-Weeks; Bruce Whittlesey; Brian McNerney; William L. Hase; Clemens Krempner; Chem.Commun. 47 (2011) 11089–; doi:10.1039/c1cc13933a

data_7106908
_publ_section_title
;
 Homoleptic tris(methoxydimethylsilyl)silanides of the alkaline earth
 metals: first zwitterionic silanides with two naked silyl anions
;
_journal_name_full               Chem.Commun.
_journal_page_first              11089
_journal_paper_doi               10.1039/c1cc13933a
_journal_volume                  47
_journal_year                    2011
_chemical_formula_sum            'C18 H54 O6 Si8 Sr'
_chemical_formula_weight         678.92
_chemical_name_systematic
;
?
;
_space_group_IT_number           64
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-C 2ac 2'
_symmetry_space_group_name_H-M   'C m 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            4
_cell_length_a                   16.8439(16)
_cell_length_b                   12.8565(12)
_cell_length_c                   16.9429(16)
_cell_measurement_temperature    150(2)
_cell_volume                     3669.0(6)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_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  0.0398
_diffrn_reflns_av_sigmaI/netI    0.0174
_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            13774
_diffrn_reflns_theta_full        22.57
_diffrn_reflns_theta_max         22.57
_diffrn_reflns_theta_min         2.33
_exptl_absorpt_coefficient_mu    3.196
_exptl_absorpt_correction_T_max  0.6305
_exptl_absorpt_correction_T_min  0.3908
_exptl_crystal_density_diffrn    1.229
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             1440
_exptl_crystal_size_max          0.36
_exptl_crystal_size_mid          0.19
_exptl_crystal_size_min          0.16
_refine_diff_density_max         0.660
_refine_diff_density_min         -0.237
_refine_diff_density_rms         0.053
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.028
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     155
_refine_ls_number_reflns         1259
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.028
_refine_ls_R_factor_all          0.0460
_refine_ls_R_factor_gt           0.0349
_refine_ls_shift/su_max          0.052
_refine_ls_shift/su_mean         0.006
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0453P)^2^+11.5346P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0869
_refine_ls_wR_factor_ref         0.0950
_reflns_number_gt                1044
_reflns_number_total             1259
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c1cc13933a.txt
_cod_data_source_block           cksrcmcabrw
_cod_database_code               7106908