#------------------------------------------------------------------------------ #$Date: 2025-08-19 07:12:48 +0100 (Tue, 19 Aug 2025) $ #$Revision: 301798 $ #$URL: svn://www.crystallography.net/cod/cif/2/01/01/2010158.cif $ #------------------------------------------------------------------------------ # # This file is available in the Crystallography Open Database (COD), # http://www.crystallography.net/. The original data for this entry # were provided by IUCr Journals, http://journals.iucr.org/. # # The file may be used within the scientific community so long as # proper attribution is given to the journal article from which the # data were obtained. # data_2010158 loop_ _publ_author_name 'T\"ornroos, K.W.' _publ_section_title ; Octahydridosilasesquioxane determined by neutron diffraction ; _journal_issue 11 _journal_name_full 'Acta Crystallographica Section C' _journal_page_first 1646 _journal_page_last 1648 _journal_paper_doi 10.1107/S0108270194005342 _journal_volume 50 _journal_year 1994 _chemical_formula_moiety 'H8 O12 Si8' _chemical_formula_sum 'H8 O12 Si8' _chemical_formula_weight 424.74 _space_group_crystal_system trigonal _space_group_IT_number 148 _space_group_name_Hall '-R 3' _space_group_name_H-M_alt 'R -3 :H' _atom_type_scat_source ; Nuclear coherent scattering lengths from Koester, Rauch, Herkens & Schr\"oder (1981) ; _cell_angle_alpha 90. _cell_angle_beta 90. _cell_angle_gamma 120. _cell_formula_units_Z 3 _cell_length_a 9.0530(10) _cell_length_b 9.0530(10) _cell_length_c 15.1490(10) _cell_measurement_reflns_used 12 _cell_measurement_temperature 29.0(5) _cell_measurement_theta_max 33.25 _cell_measurement_theta_min 20.13 _cell_volume 1075.23(18) _diffrn_measurement_device 'Huber four-circle' _diffrn_measurement_method \w/2\q _diffrn_radiation_probe neutron _diffrn_radiation_type neutron _diffrn_radiation_wavelength 1.215 _diffrn_reflns_av_R_equivalents 0.0552 _diffrn_reflns_limit_h_max 9 _diffrn_reflns_limit_h_min -10 _diffrn_reflns_limit_k_max 5 _diffrn_reflns_limit_k_min -10 _diffrn_reflns_limit_l_max 19 _diffrn_reflns_limit_l_min -19 _diffrn_reflns_number 790 _diffrn_reflns_theta_max 53.38 _diffrn_standards_decay_% <+-1 _exptl_absorpt_coefficient_mu 0.088 _exptl_absorpt_correction_T_max 0.9029 _exptl_absorpt_correction_T_min 0.8618 _exptl_absorpt_correction_type analytical _exptl_crystal_colour colourless _exptl_crystal_density_diffrn 1.968 _exptl_crystal_description rhombic _exptl_crystal_size_max 1.68 _exptl_crystal_size_mid 1.53 _exptl_crystal_size_min 1.23 _refine_ls_extinction_coef 1.31(6) _refine_ls_extinction_method 'SHELXL92 (Sheldrick, 1992)' _refine_ls_goodness_of_fit_obs 1.122 _refine_ls_hydrogen_treatment refall _refine_ls_number_parameters 44 _refine_ls_number_reflns 364 _refine_ls_R_factor_obs 0.0310 _refine_ls_shift/esd_max 0.000 _refine_ls_structure_factor_coef Fsqd _refine_ls_weighting_scheme ; 1/[\s^2^(F~o~^2^) + (0.0204P)^2^ + 0.01P] where P = (F~o~^2^ + 2F~c~^2^)/3 ; _refine_ls_wR_factor_obs 0.0526 _reflns_number_observed 364 _reflns_number_total 569 _reflns_observed_criterion I>3\s(I) _cod_data_source_file cr1105.cif _cod_data_source_block cr1105_structure_1_of_1 _cod_depositor_comments ; Changing the space group from '-P 3' to '-R 3' after consulting the original publication. All related space group information was changed accordingly. Antanas Vaitkus, 2017-07-06 The following automatic conversions were performed: '_cell_measurement_temperature' value '29+-0.5' was changed to '29.0(5)' - precision was estimated. Automatic conversion script Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana The following automatic conversions were performed: '_cell_measurement_temperature' value '29+-0.5' was changed to '29.0(5)' - precision was estimated. Automatic conversion script Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana ; _cod_original_cell_volume 1075.2(2) _cod_original_sg_symbol_H-M 'R -3' _cod_database_code 2010158 loop_ _space_group_symop_id _space_group_symop_operation_xyz 1 x,y,z 2 -y,x-y,z 3 -x+y,-x,z 4 -x,-y,-z 5 y,-x+y,-z 6 x-y,x,-z 7 x+2/3,y+1/3,z+1/3 8 -y+2/3,x-y+1/3,z+1/3 9 -x+y+2/3,-x+1/3,z+1/3 10 -x+2/3,-y+1/3,-z+1/3 11 y+2/3,-x+y+1/3,-z+1/3 12 x-y+2/3,x+1/3,-z+1/3 13 x+1/3,y+2/3,z+2/3 14 -y+1/3,x-y+2/3,z+2/3 15 -x+y+1/3,-x+2/3,z+2/3 16 -x+1/3,-y+2/3,-z+2/3 17 y+1/3,-x+y+2/3,-z+2/3 18 x-y+1/3,x+2/3,-z+2/3 loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Si(1) .0000 .0000 .32152(18) .0049(5) Si(2) .31958(19) .20905(19) .44037(10) .0048(3) O(1) .19471(14) .11230(15) .35740(8) .0083(3) O(2) .31997(15) .06903(14) .50720(8) .0080(3) H(1) .0000 .0000 .2252(3) .0222(8) H(2) .4934(3) .3218(3) .40885(16) .0218(5) loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle_site_symmetry_3 _geom_angle _geom_angle_publ_flag Si(1) O(1) Si(2) . 147.25(13) yes Si(2) O(2) Si(2) 3_556 147.45(13) yes O(1) Si(1) O(1) . 109.41(10) yes O(1) Si(2) O(2) . 109.53(10) yes O(1) Si(2) O(2) 5_556 109.45(10) yes O(2) Si(2) O(2) 5_556 109.14(10) yes H(1) Si(1) O(1) . 109.53(10) yes H(2) Si(2) O(1) . 109.86(14) yes H(2) Si(2) O(2) . 109.07(14) yes H(2) Si(2) O(2) . 109.77(14) yes loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_site_symmetry_2 _geom_bond_distance _geom_bond_publ_flag Si(1) O(1) . 1.6260(10) yes Si(2) O(1) . 1.623(2) yes Si(2) O(2) . 1.624(2) yes Si(2) O(2) 5_556 1.628(2) yes Si(1) H(1) . 1.459(5) yes Si(2) H(2) . 1.463(3) yes loop_ _cod_related_entry_id _cod_related_entry_database _cod_related_entry_code 1 PubChem 25137924