α- and γ-Polymorphs of Dimethyl 9-Chloromethyl-9,10-dihydro-9,10-ethenoanthracene-11,12-dicarboxylate
Jones, R.; Rettig, S. J.; Trotter, J.; Acta Crystallographica Section C 51 (1995) 2392–2395; doi:10.1107/S0108270195005336

data_2004129
_publ_section_title
;
 \a- and \g-Polymorphs of Dimethyl
 9-Chloromethyl-9,10-dihydro-9,10-ethenoanthracene-11,12-dicarboxylate
;
_journal_issue                   11
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              2392
_journal_page_last               2395
_journal_paper_doi               10.1107/S0108270195005336
_journal_volume                  51
_journal_year                    1995
_chemical_formula_moiety         'C21 H17 Cl O4'
_chemical_formula_sum            'C21 H17 Cl O4'
_chemical_formula_weight         368.82
_chemical_melting_point          442.0(10)
_chemical_name_systematic
;
Dimethyl 9-chloromethyl-9,10-dihydro-9,10-ethenoanthracene-
11,12-dicarboxylate
;
_space_group_IT_number           14
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_cell_angle_alpha                90
_cell_angle_beta                 108.11(1)
_cell_angle_gamma                90
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_cell_length_b                   10.513(1)
_cell_length_c                   17.813(1)
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_cell_measurement_temperature    294
_cell_measurement_theta_max      51
_cell_measurement_theta_min      48
_cell_volume                     3657.7(5)
_computing_cell_refinement
' TEXSAN (Molecular Structure Corporation, 1985)'
_computing_data_collection
' TEXSAN (Molecular Structure Corporation, 1985)'
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' TEXSAN (Molecular Structure Corporation, 1985)'
_computing_molecular_graphics
' TEXSAN (Molecular Structure Corporation, 1985)'
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' TEXSAN (Molecular Structure Corporation, 1985)'
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' TEXSAN (Molecular Structure Corporation, 1985)'
_diffrn_ambient_temperature      294
_diffrn_measurement_device       'Rigaku AFC6S'
_diffrn_measurement_method       '\w/2\q scan'
_diffrn_radiation_monochromator  graphite
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_exptl_absorpt_correction_type
' empirical \y scans (TEXSAN; Molecular Structure Corporation, 1985)'
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' TEXSAN (Molecular Structure Corporation, 1985)'
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_reflns_observed_criterion       I>3\s(I)
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_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value '441-443K' was changed to '442.0(10)'
- the average value was taken and precision was estimated.

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 '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        3658.0(10)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2004129