1,2;3,4-Bis{8',11'-dioxa[4.3.3]propella(3',4')}benzene: a Bis(propellene) from Prehnitene
Stadnicka, K.; Zeslawski, W.; Acta Crystallographica Section C 51 (1995) 2377–2381; doi:10.1107/S0108270195007402

data_2004080
_publ_section_title
;
 1,2;3,4-Bis{8',11'-dioxa[4.3.3]propella(3',4')}benzene: a
 Bis(propellene) from Prehnitene
;
_journal_issue                   11
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              2377
_journal_page_last               2381
_journal_paper_doi               10.1107/S0108270195007402
_journal_volume                  51
_journal_year                    1995
_chemical_formula_moiety         'C22 H26 O4'
_chemical_formula_sum            'C22 H26 O4'
_chemical_formula_weight         354.43
_chemical_melting_point          403.5(5)
_chemical_name_common
1,2;3,4-Bis(8',11'-dioxa[4.3.3]propella(3',4'))benzene
_chemical_name_systematic
;
1H,3H,4H,7H,8H,10H,11H,12H-3a,12a:7a,10a-Bis(methanoxymethano)phenanthro
[2,3-c:6,7-c']difuran
;
_space_group_IT_number           29
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2ac'
_symmetry_space_group_name_H-M   'P c a 21'
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   12.380(2)
_cell_length_b                   11.194(2)
_cell_length_c                   26.892(5)
_cell_measurement_reflns_used    35
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      12.2
_cell_measurement_theta_min      2.8
_cell_volume                     3726.7(11)
_computing_cell_refinement       'KUMA KM-4 software'
_computing_data_collection       'KUMA KM-4 software'
_computing_data_reduction        'DATARED KUMA KM-4 software'
_computing_molecular_graphics    'ORTEPII (Johnson, 1976)'
_computing_publication_material  SHELXL93
_computing_structure_refinement  'SHELXL93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measurement_device       'KUMA KM-4'
_diffrn_measurement_method       '\w/2\q scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a~1~
_diffrn_radiation_wavelength     0.70930
_diffrn_reflns_av_R_equivalents  0.0203
_diffrn_reflns_av_sigmaI/netI    0.0405
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       0
_diffrn_reflns_limit_l_min       -32
_diffrn_reflns_number            3003
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.51
_diffrn_standards_decay_%        'no decay, variation less than 1.5'
_diffrn_standards_interval_count 'monitored every 50 reflections'
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.086
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.263
_exptl_crystal_density_meas      1.26(2)
_exptl_crystal_density_method    'flotation in aqueous solution of KI'
_exptl_crystal_description       plate
_exptl_crystal_F_000             1520
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.175
_refine_diff_density_min         -0.119
_refine_ls_abs_structure_details 'Flack (1983)'
_refine_ls_abs_structure_Flack   0.46(1.80)
_refine_ls_extinction_coef       0.0043(7)
_refine_ls_extinction_method     'SHELXL93 (Sheldrick, 1993)'
_refine_ls_goodness_of_fit_all   1.066
_refine_ls_goodness_of_fit_obs   1.146
_refine_ls_hydrogen_treatment
'H atoms refined isotropically; riding model for H521 and H522 only'
_refine_ls_matrix_type           full
_refine_ls_number_parameters     679
_refine_ls_number_reflns         2270
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.078
_refine_ls_restrained_S_obs      1.146
_refine_ls_R_factor_all          0.0593
_refine_ls_R_factor_obs          0.0317
_refine_ls_shift/esd_max         -0.037
_refine_ls_shift/esd_mean        0.003
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0552P)^2^] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0809
_refine_ls_wR_factor_obs         0.0709
_reflns_number_observed          1755
_reflns_number_total             2271
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            ab1266.cif
_cod_data_source_block           C22H26O4
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
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_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_chemical_melting_point' value '403-404 K' was changed to '403.5(5)'
- the average value was taken and precision was
estimated.

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' 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 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc w =
1/[\s^2^(Fo^2^)+(0.0552P)^2^] where P = (Fo^2^+2Fc^2^)/3' 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^(Fo^2^)+(0.0552P)^2^]
where P = (Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_database_code               2004080