Biguanide and squaric acid as pH-dependent building blocks in crystal engineering
Şerb, Mihaela-Diana; Kalf, Irmgard; Englert, Ulli; CrystEngComm 16 (2014) 10631–; doi:10.1039/C4CE01643B

data_7218480
_publ_section_title
;
 Biguanide and squaric acid as pH-dependent building blocks in crystal
 engineering
;
_journal_issue                   46
_journal_name_full               CrystEngComm
_journal_page_first              10631
_journal_paper_doi               10.1039/C4CE01643B
_journal_volume                  16
_journal_year                    2014
_chemical_formula_moiety         'C4 H13 N5, C4 O4, 2(H2 O)'
_chemical_formula_sum            'C8 H17 N5 O6'
_chemical_formula_weight         279.27
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           29
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2ac'
_symmetry_space_group_name_H-M   'P c a 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.809(2)
_cell_length_b                   13.372(2)
_cell_length_c                   7.3552(11)
_cell_measurement_reflns_used    1776
_cell_measurement_temperature    130(2)
_cell_measurement_theta_max      21.29
_cell_measurement_theta_min      3.05
_cell_volume                     1259.8(3)
_computing_cell_refinement       'SAINT-Plus (Bruker, 1999)'
_computing_data_collection       'SMART (Bruker, 2001)'
_computing_data_reduction        'SAINT-Plus (Bruker, 1999)'
_computing_molecular_graphics    'PLATON (Spek, 2009)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      130(2)
_diffrn_measured_fraction_theta_full .999
_diffrn_measured_fraction_theta_max .999
_diffrn_measurement_device_type  'Bruker SMART APEX CCD'
_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  0.0838
_diffrn_reflns_av_sigmaI/netI    0.0749
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            14347
_diffrn_reflns_theta_full        26.49
_diffrn_reflns_theta_max         26.49
_diffrn_reflns_theta_min         2.20
_diffrn_standards_decay_%        'no decay'
_exptl_absorpt_coefficient_mu    0.126
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.472
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       fragment
_exptl_crystal_F_000             592
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.03
_refine_diff_density_max         .230
_refine_diff_density_min         -.170
_refine_diff_density_rms         .045
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.4(15)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.910
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     218
_refine_ls_number_reflns         2607
_refine_ls_number_restraints     12
_refine_ls_restrained_S_all      0.909
_refine_ls_R_factor_all          0.0643
_refine_ls_R_factor_gt           0.0459
_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^)+(0.0350P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0806
_refine_ls_wR_factor_ref         0.0856
_reflns_number_gt                1985
_reflns_number_total             2607
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c4ce01643b2.cif
_cod_data_source_block           1b
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/usr/data/users/saulius/crontab/automatic-downloads/rss-feeds/RSC/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 2827 2014-09-09 07:05:25Z andrius 

 Adding full bibliography for 7218480--7218488.cif.
;
_cod_original_sg_symbol_Hall     P2c-2ac
_cod_original_sg_symbol_H-M      Pca21
_cod_database_code               7218480