A novel heterometallic alkoxide: lithium‒potassium tert-butoxide [(ButO)8Li4K4]
Clegg, William; Liddle, Stephen T.; Drummond, Allison M.; Mulvey, Robert E.; Robertson, Alan; Chemical Communications  (1999) 1569–; doi:10.1039/a904800f

data_7115200
_publ_section_title
;
 A novel heterometallic alkoxide: lithium--potassium tert-butoxide
 [(ButO)8Li4K4]
;
_journal_issue                   16
_journal_name_full               'Chemical Communications'
_journal_page_first              1569
_journal_paper_doi               10.1039/a904800f
_journal_year                    1999
_chemical_formula_sum            'C32 H72 K4 Li4 O8'
_chemical_formula_weight         769.06
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           11
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yb'
_symmetry_space_group_name_H-M   'P 1 21/m 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                 110.166(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   11.5194(6)
_cell_length_b                   17.1506(10)
_cell_length_c                   13.0058(7)
_cell_measurement_reflns_used    10011
_cell_measurement_temperature    160(2)
_cell_measurement_theta_max      29.00
_cell_measurement_theta_min      2.90
_cell_volume                     2412.0(2)
_computing_cell_refinement       'local programs'
_computing_data_collection       'Siemens SMART'
_computing_data_reduction        'Siemens SAINT'
_computing_molecular_graphics    'Siemens SHELXTL'
_computing_publication_material  'SHELXTL and local programs'
_computing_structure_refinement  'Siemens SHELXTL'
_computing_structure_solution    'Siemens SHELXTL'
_diffrn_ambient_temperature      160(2)
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_device_type  'Siemens SMART CCD diffractometer'
_diffrn_measurement_method       '\w rotation with narrow frames'
_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  0.0192
_diffrn_reflns_av_sigmaI/netI    0.0262
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       6
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            10325
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.88
_diffrn_standards_decay_%        0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.405
_exptl_absorpt_correction_T_max  0.9162
_exptl_absorpt_correction_T_min  0.7874
_exptl_absorpt_correction_type   empirical
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.059
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             832
_exptl_crystal_size_max          0.62
_exptl_crystal_size_mid          0.44
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.231
_refine_diff_density_min         -0.309
_refine_diff_density_rms         0.039
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.035
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     266
_refine_ls_number_reflns         4372
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.035
_refine_ls_R_factor_all          0.0441
_refine_ls_R_factor_gt           0.0324
_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^)+(0.0537P)^2^+0.0508P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0853
_refine_ls_wR_factor_ref         0.0880
_reflns_number_gt                3351
_reflns_number_total             4372
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            904800f.txt
_cod_data_source_block           rem218
_cod_original_sg_symbol_H-M      P2(1)/m
_cod_database_code               7115200