(18-Crown-6)-bis(tetrahydrofuran)potassium iodide
Liddle, Stephen T.; Clegg, William; Acta Crystallographica Section E 59 (2003) m1184–m1186; doi:10.1107/S160053680302676X

data_2202733
_publ_section_title
;
 (18-Crown-6)-bis(tetrahydrofuran)potassium iodide
;
_journal_issue                   12
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              m1184
_journal_page_last               m1186
_journal_paper_doi               10.1107/S160053680302676X
_journal_volume                  59
_journal_year                    2003
_chemical_formula_iupac          '[K (C12 H24 O6) (C4 H8 O)2] I'
_chemical_formula_moiety         'C20 H40 K O8 +, I -'
_chemical_formula_sum            'C20 H40 I K O8'
_chemical_formula_weight         574.52
_chemical_name_systematic
;
(18-Crown-6)-bis(tetrahydrofuran)potassium iodide
;
_space_group_IT_number           92
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  'P 4abw 2nw'
_symmetry_space_group_name_H-M   'P 41 21 2'
_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                   12.2645(15)
_cell_length_b                   12.2645(15)
_cell_length_c                   34.372(6)
_cell_measurement_reflns_used    6732
_cell_measurement_temperature    160(2)
_cell_measurement_theta_max      28.57
_cell_measurement_theta_min      2.75
_cell_volume                     5170.2(13)
_computing_cell_refinement       'SAINT (Bruker, 2001)'
_computing_data_collection       'SMART (Bruker, 2001)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    SHELXTL
_computing_publication_material  'SHELXTL and local programs'
_computing_structure_refinement  SHELXTL
_computing_structure_solution    'SHELXTL (Sheldrick, 2001)'
_diffrn_ambient_temperature      160(2)
_diffrn_detector_area_resol_mean 8.192
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker SMART 1K CCD diffractometer'
_diffrn_measurement_method       'thin-slice \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0496
_diffrn_reflns_av_sigmaI/netI    0.0340
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       39
_diffrn_reflns_limit_l_min       -40
_diffrn_reflns_number            26143
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.76
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    1.438
_exptl_absorpt_correction_T_max  0.46
_exptl_absorpt_correction_T_min  0.29
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 2002)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.476
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'square antiprism'
_exptl_crystal_F_000             2368
_exptl_crystal_size_max          0.66
_exptl_crystal_size_mid          0.62
_exptl_crystal_size_min          0.54
_refine_diff_density_max         0.857
_refine_diff_density_min         -0.683
_refine_ls_abs_structure_details 'Flack (1983); 1862 Friedel pairs'
_refine_ls_abs_structure_Flack   0.00(3)
_refine_ls_extinction_coef       0.00029(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXTL97
_refine_ls_goodness_of_fit_ref   1.104
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     273
_refine_ls_number_reflns         4570
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.104
_refine_ls_R_factor_all          0.0443
_refine_ls_R_factor_gt           0.0371
_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^)+(0.0303P)^2^+5.4555P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0785
_refine_ls_wR_factor_ref         0.0809
_reflns_number_gt                4051
_reflns_number_total             4570
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            lh6144.cif
_cod_data_source_block           I
_cod_database_code               2202733
_cod_database_fobs_code          2202733