A Diels-Alder super diene breaking benzene into C2H2 and C4H4 units.
Inagaki, Yusuke; Nakamoto, Masaaki; Sekiguchi, Akira; Nature communications 5 (2014) 3018–; doi:10.1038/ncomms4018

data_1513794
_publ_section_title
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 A Diels-Alder super diene breaking benzene into C2H2 and C4H4 units.
;
_journal_name_full               'Nature communications'
_journal_page_first              3018
_journal_paper_doi               10.1038/ncomms4018
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_journal_year                    2014
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_exptl_absorpt_process_details
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SADABS Sheldrick 1996
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_exptl_crystal_colour            colorless
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_exptl_crystal_density_meas      ?
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_refine_ls_structure_factor_coef Fsqd
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'calc w=1/[\s^2^(Fo^2^)+(0.0679P)^2^+3.4861P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1190
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_cod_data_source_file            ncomms4018-s2.cif
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_cod_depositor_comments
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The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/usr/data/users/saulius/automatic-downloads/current/Nature/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 2281 2013-09-26 08:29:07Z andrius 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_sg_symbol_H-M      'Pbca '
_cod_database_code               1513794