3,3,18,18-Tetramethyl-1,5,16,20-tetraoxadispiro[5.8.5.8]octacosane
Lewis, T. J.; Rettig, S. J.; Scheffer, J. R.; Trotter, J.; Acta Crystallographica Section C 51 (1995) 2688–2690; doi:10.1107/S0108270195008201

data_2004247
_publ_contact_author
;
    Professor James Trotter
    Department of Chemistry
    University of British Columbia
    Vancouver, B.C.
    Canada V6T 1Z1
;
_publ_section_title
;
 3,3,18,18-Tetramethyl-1,5,16,20-tetraoxadispiro[5.8.5.8]octacosane
;
_journal_issue                   12
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              2688
_journal_page_last               2690
_journal_paper_doi               10.1107/S0108270195008201
_journal_volume                  51
_journal_year                    1995
_chemical_formula_moiety         'C28 H52 O4'
_chemical_formula_sum            'C28 H52 O4'
_chemical_formula_weight         452.72
_chemical_name_systematic
;
3,3,18,18-Tetramethyl-1,5,16,20-tetraoxadispiro[5,8,5,8]
octacosane
OR
5,5-Dimethyl-1,3-dioxacyclohexan-2-spiro-1'-cyclooctadecan-
10'-spiro-2"-5",5"-dimethyl-1",3"-dioxacyclohexane
OR
Dispiro[5,5-dimethyl-1,3-dioxacyclohexane-2,1'-cyclooctadecan-
10',2"-5",5"-dimethyl-1",3"-dioxacyclohexane]
;
_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_type_scat_source           IntTabIV
_cell_angle_alpha                90.27(1)
_cell_angle_beta                 104.32(1)
_cell_angle_gamma                109.86(1)
_cell_formula_units_Z            1
_cell_length_a                   10.718(1)
_cell_length_b                   13.050(1)
_cell_length_c                   5.5074(4)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    294
_cell_measurement_theta_max      57.4
_cell_measurement_theta_min      46.4
_cell_volume                     698.66(12)
_computing_cell_refinement       'MSC/AFC Diffractometer Control Software'
_computing_data_collection
;MSC/AFC Diffractometer Control Software (Molecular Structure Corporation,
 1988)
;
_computing_data_reduction
'TEXSAN (Molecular Structure Corporation, 1990)'
_computing_publication_material  TEXSAN
_computing_structure_refinement  TEXSAN
_computing_structure_solution    TEXSAN
_diffrn_ambient_temperature      294
_diffrn_measurement_device       AFC6S
_diffrn_measurement_method       '\w-2\q scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'X-ray tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.019
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_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       6
_diffrn_reflns_limit_l_min       -6
_diffrn_reflns_number            3165
_diffrn_reflns_theta_max         77.5
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 250
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.51
_exptl_absorpt_correction_T_max  1.00
_exptl_absorpt_correction_T_min  0.72
_exptl_absorpt_correction_type   'DIFABS (Walker & Stuart, 1983)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.076
_exptl_crystal_description       needle
_exptl_crystal_F_000             252
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.25
_refine_diff_density_max         0.17
_refine_diff_density_min         -0.15
_refine_ls_extinction_coef       '1.4 x 10^-4^'
_refine_ls_extinction_method     'Zachariasen (1968) type 2 Gaussian isotropic'
_refine_ls_goodness_of_fit_obs   2.9
_refine_ls_hydrogen_treatment    refxyzB
_refine_ls_matrix_type           full
_refine_ls_number_constraints    0
_refine_ls_number_parameters     250
_refine_ls_number_reflns         2325
_refine_ls_number_restraints     0
_refine_ls_R_factor_obs          0.042
_refine_ls_shift/esd_max         0.00
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     'w = 1/\s^2^(F)'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_obs         0.056
_reflns_number_observed          2325
_reflns_number_total             2844
_reflns_observed_criterion       3\s(I)
_cod_data_source_file            fg1091.cif
_cod_data_source_block           18ring
_cod_depositor_comments
;
The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value '1/\s^2^(F)' 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^(F)'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        698.60(10)
_cod_database_code               2004247