Synthesis and Structure of Cyclic Aluminum Disiloxides
Krempner, C.; Reinke, H.; Weichert, K.; Organometallics 26 (2007) 1386–; doi:10.1021/om060969h

data_4072718
_publ_section_title
;
 Synthesis and Structure of Cyclic Aluminum Disiloxides
;
_journal_issue                   6
_journal_name_full               Organometallics
_journal_page_first              1386
_journal_paper_doi               10.1021/om060969h
_journal_volume                  26
_journal_year                    2007
_chemical_absolute_configuration ad
_chemical_formula_sum            'C40 H120 Al O4 Si20'
_chemical_formula_weight         1254.14
_chemical_name_systematic
; 
 Hydrogen-(2R*,3R*,7S*,8S*)-2,3,7,8-tetramethyl-2,3,7,8-tetrakis[tris
(trimethylsilyl)silyl]-5-aluminata-1,4,6,9-tetraoxa-2,3,7,8-tetrasila-
spiro[4.4]nonane 
;
_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            4
_cell_length_a                   17.864(3)
_cell_length_b                   17.864(3)
_cell_length_c                   26.009(5)
_cell_measurement_reflns_used    6487
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      22.44
_cell_measurement_theta_min      2.41
_cell_volume                     8300(3)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'Bruker SHELXTL'
_computing_structure_solution    'Bruker SHELXTL'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'Bruker X8Apex CCD'
_diffrn_measurement_method       'phi and omega scans'
_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  0.0380
_diffrn_reflns_av_sigmaI/netI    0.0368
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            24332
_diffrn_reflns_theta_full        22.48
_diffrn_reflns_theta_max         22.48
_diffrn_reflns_theta_min         2.67
_exptl_absorpt_coefficient_mu    0.342
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.004
_exptl_crystal_description       prism
_exptl_crystal_F_000             2740
_exptl_crystal_size_max          0.53
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.218
_refine_diff_density_min         -0.284
_refine_diff_density_rms         0.057
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.0(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.134
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     294
_refine_ls_number_reflns         5382
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.134
_refine_ls_R_factor_all          0.0780
_refine_ls_R_factor_gt           0.0654
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0138P)^2^+23.1770P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1400
_refine_ls_wR_factor_ref         0.1455
_reflns_number_gt                4602
_reflns_number_total             5382
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om060969hsi20061022_102117.cif
_cod_data_source_block           w303
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Tetragonal' changed to 'tetragonal'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        8301(2)
_cod_original_sg_symbol_H-M      'P4(1)2(1)2 '
_cod_database_code               4072718