Crystal structure of diaquabis(m-4-carboxy-2-ethyl-1H-imidazole-5-carboxylato-k3N3,O4:O5)calcium(II), Ca(H2O)2(C7H7N2O4)2
Da-Min Tian; Yin-Feng Li; Cheng-Jun Hao; Zeitschrift für Kristallographie - New Crystal Structures 225 (2010) 403–; doi:

data_8102722
_publ_section_title
;
 Crystal structure of
 diaquabis(m-4-carboxy-2-ethyl-1H-imidazole-5-carboxylato-k3N3,O4:O5)calcium(II),
 Ca(H2O)2(C7H7N2O4)2
;
_journal_issue                   2
_journal_name_full
'Zeitschrift f\"ur Kristallographie - New Crystal Structures'
_journal_page_first              403
_journal_volume                  225
_journal_year                    2010
_chemical_formula_moiety         'C14 H18 Ca N4 O10'
_chemical_formula_sum            'C14 H18 Ca N4 O10'
_chemical_formula_weight         442.40
_chemical_name_systematic
; 
Poly[diaquabis(\m-4-carboxy-2-ethyl-1H-imidazole
-5-carboxylato-k^3^N^3^,O^4^:O^5^)calcium(II)], 
[Ca(C~7~H~7~N~2~O~4~)~2~(H~2~O)~2~]~n~ 
;
_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                 99.1910(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.2479(13)
_cell_length_b                   13.3451(15)
_cell_length_c                   11.3150(10)
_cell_measurement_reflns_used    2051
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      23.917
_cell_measurement_theta_min      2.483
_cell_volume                     1825.7(3)
_computing_cell_refinement       'SAINT (Bruker, 2007)'
_computing_data_collection       'SMART (Bruker, 2007)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    'SHELXTL (Sheldrick, 2008)'
_computing_publication_material  SHELXTL
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'SMART 1000 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  0.0275
_diffrn_reflns_av_sigmaI/netI    0.0303
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            4509
_diffrn_reflns_theta_full        24.99
_diffrn_reflns_theta_max         24.99
_diffrn_reflns_theta_min         2.27
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.409
_exptl_absorpt_correction_T_max  0.9155
_exptl_absorpt_correction_T_min  0.8374
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.610
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             920
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.23
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.241
_refine_diff_density_min         -0.272
_refine_diff_density_rms         0.059
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.093
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     133
_refine_ls_number_reflns         1613
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.093
_refine_ls_R_factor_all          0.0469
_refine_ls_R_factor_gt           0.0341
_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^)+(0.0443P)^2^+1.1127P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0804
_refine_ls_wR_factor_ref         0.0907
_reflns_number_gt                1293
_reflns_number_total             1613
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            1267-3004.cff
_cod_data_source_block           1
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               8102722