A Metastable Polymorph of Metformin Hydrochloride: Isolation and Characterization Using Capillary Crystallization and Thermal Microscopy Techniques
Childs, Scott L.; Chyall, Leonard J.; Dunlap, Jeanette T.; Coates, David A.; Stahly, Barbara C.; Stahly, G. Patrick; Crystal Growth & Design 4 (2004) 441–; doi:10.1021/cg034243p

data_4505342
_publ_section_title
;
 A Metastable Polymorph of Metformin Hydrochloride:&#x2009; Isolation and
 Characterization Using Capillary Crystallization and Thermal Microscopy
 Techniques
;
_journal_issue                   3
_journal_name_full               'Crystal Growth &amp; Design'
_journal_page_first              441
_journal_paper_doi               10.1021/cg034243p
_journal_volume                  4
_journal_year                    2004
_chemical_formula_moiety         'C4 H12 Cl N5'
_chemical_formula_sum            'C4 H12 Cl N5'
_chemical_formula_weight         165.64
_chemical_melting_point          505.15
_chemical_name_common            'Metformin HCl form I'
_chemical_name_systematic
;
 N,N-Dimethylimidodicarbonimidic diamide hydrochloride
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/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                 114.48
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.9231(12)
_cell_length_b                   13.894(2)
_cell_length_c                   7.9231(12)
_cell_measurement_reflns_used    5625
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      33.04
_cell_measurement_theta_min      2.83
_cell_volume                     793.8(2)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.943
_diffrn_measured_fraction_theta_max 0.943
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0480
_diffrn_reflns_av_sigmaI/netI    0.0535
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            10423
_diffrn_reflns_theta_full        33.04
_diffrn_reflns_theta_max         33.04
_diffrn_reflns_theta_min         2.82
_exptl_absorpt_coefficient_mu    0.418
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.386
_exptl_crystal_density_meas      0
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             352
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.14
_exptl_crystal_size_min          0.07
_refine_diff_density_max         0.438
_refine_diff_density_min         -0.307
_refine_diff_density_rms         0.069
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.078
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     139
_refine_ls_number_reflns         2836
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.078
_refine_ls_R_factor_all          0.0445
_refine_ls_R_factor_gt           0.0354
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0300P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0763
_refine_ls_wR_factor_ref         0.0781
_reflns_number_gt                2309
_reflns_number_total             2836
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            cg034243psi20031203_050541.cif
_cod_data_source_block           methcl_I
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value '232C' was changed to '505.15' - it
was converted from degrees Celsius(C) to
Kelvins(K).

'_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      P2(1)/c
_cod_database_code               4505342