Diseleno[2,3-b:3',2'-d]selenophene and Diseleno[2,3-b:3',2'-d] thiophene: Building Blocks for the Construction of [7]Helicenes.
Xu, Wan; Wu, Longlong; Fang, Maohong; Ma, Zhiying; Shan, Zhen; Li, Chunli; Wang, Hua; The Journal of organic chemistry 82 (2017) 11192–11197; doi:10.1021/acs.joc.7b01362

data_4032952
_publ_section_title
;
 Diseleno[2,3-b:3',2'-d]selenophene and Diseleno[2,3-b:3',2'-d] thiophene:
 Building Blocks for the Construction of [7]Helicenes.
;
_journal_issue                   20
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              11192
_journal_page_last               11197
_journal_paper_doi               10.1021/acs.joc.7b01362
_journal_volume                  82
_journal_year                    2017
_chemical_formula_sum            'C24 H22 S2 Se4 Si2'
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_computing_cell_refinement       'Bruker SMART'
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_computing_structure_refinement  'Bruker SHELXTL'
_computing_structure_solution    'Bruker SHELXTL'
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_exptl_crystal_colour            colorless
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_exptl_crystal_density_method    'not measured'
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_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0377P)^2^+2.8500P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0770
_refine_ls_wR_factor_ref         0.0843
_reflns_number_gt                3419
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_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo7b01362_si_002.cif
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_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Trigonal' changed to 'trigonal'
according to
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

'_exptl_absorpt_correction_type' value 'Multi-scan' changed to
'multi-scan' according to
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 4973 2017-02-22 13:04:09Z antanas 

 Adding full bibliography for 4032952--4032954.cif.
;
_cod_original_cell_volume        12880(4)
_cod_original_sg_symbol_H-M      'R-3   '
_cod_database_code               4032952