An ammonium iron(II) pyrophosphate, (NH~4~)~2~[Fe~3~(P~2~O~7~)~2~(H~2~O)~2~], with a layered structure
Liu, Biao; Zhang, Xin; Wen, Lei; Sun, Wei; Huang, Ya-Xi; Acta Crystallographica Section E 68 (2012) i5–i6; doi:10.1107/S1600536811052482

data_2233136
_publ_section_title
;
 An ammonium iron(II) pyrophosphate,
 (NH~4~)~2~[Fe~3~(P~2~O~7~)~2~(H~2~O)~2~], with a layered structure
;
_journal_coeditor_code           FI2119
_journal_issue                   1
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              i5
_journal_page_last               i6
_journal_paper_doi               10.1107/S1600536811052482
_journal_volume                  68
_journal_year                    2012
_chemical_formula_iupac          '(N H4)2 [Fe3 (H2 O)2 (P2 O7)2]'
_chemical_formula_moiety         '2(H4 N +), Fe3 H4 O16 P4 2-'
_chemical_formula_sum            'Fe3 H12 N2 O16 P4'
_chemical_formula_weight         587.55
_chemical_name_systematic
;
Diammonium diaquabis(phosphato)triferrate(II)
;
_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   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 99.651(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   9.4131(17)
_cell_length_b                   8.1940(15)
_cell_length_c                   9.3987(17)
_cell_measurement_reflns_used    4127
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      28.26
_cell_measurement_theta_min      2.20
_cell_volume                     714.7(2)
_computing_cell_refinement       'SAINT (Bruker, 2001)'
_computing_data_collection       'SMART (Bruker, 2001)'
_computing_data_reduction        'SAINT (Bruker, 2001)'
_computing_molecular_graphics
'DIAMOND (Brandenburg, 2005) and ATOMS (Dowty, 2004)'
_computing_publication_material
'SHELXL-97 (Sheldrick, 2008) and WinGX (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 1.0
_diffrn_measured_fraction_theta_max 1.0
_diffrn_measurement_device_type
'Bruker Smart APEXI diffractometer equipped with CCD area-detector'
_diffrn_measurement_method
'1265 images,\f=0, 90, 180\%, and \D\w=0.3\%, \c= 54.74\%'
_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  0.0351
_diffrn_reflns_av_sigmaI/netI    0.0480
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -5
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            4127
_diffrn_reflns_theta_full        28.26
_diffrn_reflns_theta_max         28.26
_diffrn_reflns_theta_min         2.19
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    3.548
_exptl_absorpt_correction_T_max  0.808
_exptl_absorpt_correction_T_min  0.775
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   '(SMART; Bruker, 2001)'
_exptl_crystal_colour            'light yellow'
_exptl_crystal_density_diffrn    2.730
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             584
_exptl_crystal_size_max          0.08
_exptl_crystal_size_mid          0.06
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.551
_refine_diff_density_min         -0.548
_refine_ls_extinction_coef       0
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.048
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     135
_refine_ls_number_reflns         1652
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.048
_refine_ls_R_factor_all          0.0485
_refine_ls_R_factor_gt           0.0399
_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^)+(0.0331P)^2^+1.7041P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0815
_refine_ls_wR_factor_ref         0.0850
_reflns_number_gt                1417
_reflns_number_total             1652
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            fi2119.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2233136
_cod_database_fobs_code          2233136