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_1513795
_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
_journal_volume                  5
_journal_year                    2014
_chemical_formula_sum            'C21 H31 F5 Si3'
_chemical_formula_weight         462.73
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_symmetry_space_group_name_Hall  '-P 2ac 2ab'
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_cell_length_b                   12.5084(7)
_cell_length_c                   33.328(2)
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_computing_cell_refinement       'APEX2 (Bruker AXS, 2006)'
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_computing_molecular_graphics    'XSHEL (Bruker AXS,2002)'
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_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
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_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -43
_diffrn_reflns_number            25372
_diffrn_reflns_theta_full        27.55
_diffrn_reflns_theta_max         27.55
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_exptl_absorpt_process_details
; 
SADABS Sheldrick 1996 
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.265
_exptl_crystal_density_meas      ?
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_refine_ls_shift/su_mean         0.002
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0457P)^2^+2.8713P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0910
_refine_ls_wR_factor_ref         0.0937
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_reflns_number_total             5534
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ncomms4018-s3.cif
_cod_data_source_block           yi21_0m
_cod_depositor_comments
;
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_cell_volume        4860.1(5)
_cod_original_sg_symbol_H-M      'Pbca '
_cod_database_code               1513795