Intermetallic Lithium-Magnesium Hexamethyldisilazide: Synthesis and Structure, Discovery of an Oxygen-Centered Variant, and a Reaction with Benzonitrile That Produces a Novel Amidinate Cage Compound with a Trigonal Bipyramidal Li4MgO Core
Alan R. Kennedy; Robert E. Mulvey; René B. Rowlings; Journal of the American Chemical Society 120 (1998) 7816–7824; doi:10.1021/ja980561e

data_4116796
_publ_section_title
;
 Intermetallic Lithium-Magnesium Hexamethyldisilazide: Synthesis and
 Structure, Discovery of an Oxygen-Centered Variant, and a Reaction with
 Benzonitrile That Produces a Novel Amidinate Cage Compound with a
 Trigonal Bipyramidal Li4MgO Core
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              7816
_journal_page_last               7824
_journal_paper_doi               10.1021/ja980561e
_journal_volume                  120
_journal_year                    1998
_chemical_formula_sum            'C18 H54 Li Mg N3 Si6'
_chemical_formula_weight         512.43
_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                98.33(2)
_cell_angle_beta                 92.568(19)
_cell_angle_gamma                105.00(3)
_cell_formula_units_Z            2
_cell_length_a                   8.994(2)
_cell_length_b                   11.440(5)
_cell_length_c                   16.620(4)
_cell_measurement_reflns_used    21
_cell_measurement_temperature    123
_cell_measurement_theta_max      16.8
_cell_measurement_theta_min      13.2
_cell_volume                     1628.3(9)
_computing_data_reduction        texsan
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    SIR92
_diffrn_ambient_temperature      123(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Rigaku AFC7S'
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0690
_diffrn_reflns_av_sigmaI/netI    0.1192
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            6118
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.56
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 150
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.286
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.045
_exptl_crystal_description       fragment
_exptl_crystal_F_000             564
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.452
_refine_diff_density_min         -0.541
_refine_diff_density_rms         0.084
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.015
_refine_ls_hydrogen_treatment    calc
_refine_ls_matrix_type           full
_refine_ls_number_parameters     313
_refine_ls_number_reflns         5721
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.015
_refine_ls_R_factor_all          0.1434
_refine_ls_R_factor_gt           0.0581
_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^)+(0.0754P)^2^+1.9630P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1457
_refine_ls_wR_factor_ref         0.1724
_reflns_number_gt                3345
_reflns_number_total             5721
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ja980561e_1.cif
_cod_data_source_block           limg
_cod_depositor_comments
;
The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0754P)^2^+1.9630P] 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^)+(0.0754P)^2^+1.9630P] 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        1628.3(8)
_cod_database_code               4116796