A second monoclinic polymorph of 2-amino-4,6-dichloropyrimidine
Fun, Hoong-Kun; Chantrapromma, Suchada; Jana, Subrata; Chakrabarty, Rinku; Goswami, Shyamaprosad; Acta Crystallographica Section E 64 (2008) o1659–o1660; doi:10.1107/S1600536808023714

data_2219434
_publ_section_title
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 A second monoclinic polymorph of 2-amino-4,6-dichloropyrimidine
;
_journal_coeditor_code           SJ2524
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1659
_journal_page_last               o1660
_journal_paper_doi               10.1107/S1600536808023714
_journal_volume                  64
_journal_year                    2008
_chemical_formula_moiety         'C4 H3 Cl2 N3'
_chemical_formula_sum            'C4 H3 Cl2 N3'
_chemical_formula_weight         163.99
_chemical_melting_point_gt       492
_chemical_melting_point_lt       494
_chemical_name_systematic
;
A second monoclinic polymorph of 2-amino-4,6-dichloropyrimidine
;
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 102.193(7)
_cell_angle_gamma                90.00
_cell_formula_units_Z            16
_cell_length_a                   32.060(4)
_cell_length_b                   3.8045(6)
_cell_length_c                   21.302(3)
_cell_measurement_reflns_used    2886
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      27.50
_cell_measurement_theta_min      1.30
_cell_volume                     2539.6(6)
_computing_cell_refinement       'APEX2 (Bruker, 2005)'
_computing_data_collection       'APEX2 (Bruker, 2005)'
_computing_data_reduction        'SAINT (Bruker, 2005)'
_computing_molecular_graphics    'SHELXTL (Sheldrick, 2008)'
_computing_publication_material
;
SHELXTL and PLATON (Spek, 2003)
;
_computing_structure_refinement  'SHELXTL (Sheldrick, 2008)'
_computing_structure_solution    'SHELXTL (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_detector_area_resol_mean 8.33
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type
;
Bruker SMART APEX2 CCD area-detector diffractometer
;
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0512
_diffrn_reflns_av_sigmaI/netI    0.0495
_diffrn_reflns_limit_h_max       40
_diffrn_reflns_limit_h_min       -40
_diffrn_reflns_limit_k_max       4
_diffrn_reflns_limit_k_min       -4
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            12772
_diffrn_reflns_theta_full        27.50
_diffrn_reflns_theta_max         27.50
_diffrn_reflns_theta_min         1.30
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.921
_exptl_absorpt_correction_T_max  0.9845
_exptl_absorpt_correction_T_min  0.6203
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Bruker, 2005)'
_exptl_crystal_colour            Colorless
_exptl_crystal_density_diffrn    1.716
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Block
_exptl_crystal_F_000             1312
_exptl_crystal_size_max          0.57
_exptl_crystal_size_mid          0.14
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.222
_refine_diff_density_min         -0.244
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.024
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     187
_refine_ls_number_reflns         2886
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.024
_refine_ls_R_factor_all          0.0749
_refine_ls_R_factor_gt           0.0401
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         <0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0403P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0849
_refine_ls_wR_factor_ref         0.0975
_reflns_number_gt                1875
_reflns_number_total             2886
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            sj2524.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               2219434
_cod_database_fobs_code          2219434