6-Chloroisocytosine and 5-bromo-6-methylisocytosine: again, one or two tautomers present in the same crystal?
Gerhardt, Valeska; Bolte, Michael; Acta Crystallographica Section C 72 (2016) 84–93; doi:10.1107/S2053229615024080

data_2020337
_publ_section_title
;
 6-Chloroisocytosine and 5-bromo-6-methylisocytosine: again, one or two
 tautomers present in the same crystal?
;
_journal_coeditor_code           UK3121
_journal_issue                   1
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              84
_journal_page_last               93
_journal_paper_doi               10.1107/S2053229615024080
_journal_volume                  72
_journal_year                    2016
_chemical_formula_iupac
'C4.64 H5.27 Br0.64 Cl0.37 N3 O , C5 H6 Br N3 O'
_chemical_formula_moiety
'C4.64 H5.27 Br0.64 Cl0.37 N3 O, C5 H6 Br N3 O'
_chemical_formula_sum            'C9.64 H11.27 Br1.64 Cl0.37 N6 O2'
_chemical_formula_weight         386.58
_chemical_name_systematic
;2-amino-5-bromo-6-methylpyrimidin-4(3<i>H</i>)-one--2-amino-5-bromo-6-methylpyrimidin-4(1<i>H</i>)-one--2-amino-6-chloropyrimidin-4(3<i>H</i>)-one
(0.635/1/0.365)
;
_space_group_crystal_system      monoclinic
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_cell_length_b                   11.423(4)
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_cell_volume                     1314.9(11)
_computing_cell_refinement
;
X-AREA (Stoe & Cie, 2001)
;
_computing_data_collection
;
X-AREA (Stoe & Cie, 2001)
;
_computing_data_reduction
;
X-AREA (Stoe & Cie, 2001)
;
_computing_molecular_graphics
;
Mercury (Macrae <i>et al.</i>,  2008) and XP in SHELXTL-Plus (Sheldrick,
2008)
;
_computing_publication_material
;
publCIF (Westrip, 2010)
;
_computing_structure_refinement
;
SHELXL97 (Sheldrick, 2008)
;
_computing_structure_solution
;
SHELXS97 (Sheldrick, 2008)
;
_diffrn_ambient_temperature      173(2)
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_diffrn_measurement_device_type  'Stoe IPDSII two-circle diffractometer'
_diffrn_measurement_method       \w
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_diffrn_reflns_limit_h_min       -11
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_exptl_absorpt_process_details
;
X-AREA (Stoe & Cie, 2001)
;
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+18.9797P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1987
_refine_ls_wR_factor_ref         0.2021
_reflns_number_gt                2241
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_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            uk3121sup1.cif
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_cod_depositor_comments
;Adding full bibliography for 2020333--2020337.cif.

 Adding full bibliography for 2020333--2020337.cif.
;
_cod_database_code               2020337
_cod_database_fobs_code          2020337
_shelx_estimated_absorpt_t_min   0.318
_shelx_estimated_absorpt_t_max   0.427
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