Structures of dipotassium rubidium citrate monohydrate, K~2~RbC~6~H~5~O~7~(H~2~O), and potassium dirubidium citrate monohydrate, KRb~2~C~6~H~5~O~7~(H~2~O), from laboratory X-ray powder diffraction data and DFT calculations
Cigler, Andrew J.; Kaduk, James A.; Acta Crystallographica Section E 76 (2020) 1566–1571; doi:10.1107/S2056989020011846

data_2243580
_publ_section_title
;
 Structures of dipotassium rubidium citrate monohydrate,
 K~2~RbC~6~H~5~O~7~(H~2~O), and potassium dirubidium citrate monohydrate,
 KRb~2~C~6~H~5~O~7~(H~2~O), from laboratory X-ray powder diffraction data
 and DFT calculations
;
_journal_coeditor_code           HB7917
_journal_issue                   10
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              1566
_journal_page_last               1571
_journal_paper_doi               10.1107/S2056989020011846
_journal_volume                  76
_journal_year                    2020
_chemical_formula_iupac          '2K +, Rb +, C6 H5 O7 3-, H2 O'
_chemical_formula_moiety         '2(K +), Rb +, C6 H5 O7 3-, H2 O'
_chemical_formula_sum            'C6 H7 K2.108 O8 Rb0.892'
_chemical_formula_weight         365.78
_chemical_name_common            'Dipotassium rubidium citrate monohydrate'
_chemical_name_systematic
;
Dipotassium rubidium citrate monohydrate
;
_space_group_IT_number           14
_space_group_name_Hall           '-P 2yn'
_space_group_name_H-M_alt        'P 1 21/n 1'
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_audit_creation_method           'created in GSAS-II'
_cell_angle_alpha                90
_cell_angle_beta                 98.334(7)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   7.2407(10)
_cell_length_b                   11.8145(3)
_cell_length_c                   13.062(2)
_cell_measurement_temperature    300
_cell_volume                     1105.6(2)
_computing_molecular_graphics
;
Mercury (Macrae <i>et al.</i>,  2020), <i>Materials Studio</i>
(Dassault Systems, 2019), DIAMOND (Crystal Impact, 2015)
;
_computing_publication_material
;
publCIF (Westrip, 2010)
;
_computing_structure_refinement
;
GSAS-II (Toby & Von Dreele, 2013)
;
_computing_structure_solution
;
<i>FOX</i> (Favre-Nicolin & \<Cern\'y, 2002)
;
_diffrn_ambient_temperature      300
_diffrn_detector                 'Si strip'
_diffrn_measurement_device_type  'PANalytical Empyrean'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           K\a~1,2~
_diffrn_source                   'sealed X-ray tube'
_exptl_crystal_density_diffrn    2.1976
_pd_block_id                     2020-04-09T10:08|acig036|KadukJamesA.|NCCPAN
_pd_calc_method                  'Rietveld Refinement'
_pd_char_colour                  white
_pd_instr_dist_spec/detc         240
_pd_instr_dist_src/spec          240
_pd_instr_location               '107 WSC North Central College'
_pd_meas_2theta_range_inc        0.01671
_pd_meas_2theta_range_max        49.97251
_pd_meas_2theta_range_min        1.00840
_pd_meas_scan_method             step
_pd_phase_name                   'K2 Rb C6 H5 O7'
_pd_prep_temperature             403
_pd_proc_2theta_range_inc        0.01671
_pd_proc_2theta_range_max        49.98463
_pd_proc_2theta_range_min        1.02052
_pd_proc_info_datetime           2020-04-09T10:08
_pd_proc_ls_background_function
;
Background function: "chebyschev-1" function with 4 terms:
    2307(6), -280(6), 22(5), -43(4),
  Background peak parameters: pos, int, sig, gam:
    10.29(6), 1.13(5)e5, 2.80(23)e4, 0.100,
;
_pd_proc_ls_pref_orient_corr
;
Spherical Harmonics correction. Order = 2 Model: cylindrical
    Orientation angles: omega = 0.00; chi = 0.00; phi = 0.00;
    Coefficients:  0::C(2,0,-2) = -0.0803; 0::C(2,0,0) = 0.1239;
    0::C(2,0,2) = 0.2546;
Simple spherical harmonic correction Order = 2
    Coefficients:  0:0:C(2,-2) = 0.0000; 0:0:C(2,0) = 0.0000;
    0:0:C(2,2) = 0.0000;
;
_pd_proc_ls_profile_function
;
Finger-Cox-Jephcoat function parameters U, V, W, X, Y, SH/L:
  peak variance(Gauss) = Utan(Th)^2^+Vtan(Th)+W:
  peak HW(Lorentz) = X/cos(Th)+Ytan(Th); SH/L = S/L+H/L
  U, V, W in (centideg)^2^, X & Y in centideg
    19.949, 12.795, 0.000, 2.075, 0.000, 0.032,
  Crystallite size in microns with "isotropic" model:
  parameters: Size, G/L mix
    1.000, 1.000,
  Microstrain, "generalized" model (10^6^ * delta Q/Q)
  parameters: S400, S040, S004, S220, S202, S022, S301, S103, S121, G/L mix
    21847.124, 158.305, 5787.320, 10788.591, 22832.702, -379.772,
    23098.342, 3225.801, 2172.138, 1.000,
;
_pd_proc_ls_prof_R_factor        0.02566
_pd_proc_ls_prof_wR_expected     0.01789
_pd_proc_ls_prof_wR_factor       0.03308
_pd_proc_number_of_points        2931
_pd_spec_mounting                'Glass capillary'
_pd_spec_mount_mode              transmission
_pd_spec_shape                   cylinder
_pd_spec_size_axial              12
_pd_spec_size_equat              0.5
_pd_spec_size_thick              0.5
_refine_ls_goodness_of_fit_all   1.884
_refine_ls_hydrogen_treatment    refU
_refine_ls_matrix_type           full
_refine_ls_number_constraints    15
_refine_ls_number_parameters     70
_refine_ls_number_restraints     29
_refine_ls_shift/su_max          0.2054
_refine_ls_weighting_scheme      sigma
_refine_ls_wR_factor_obs         0.03327
_reflns_number_total             1960
_cod_data_source_file            hb7917sup1.cif
_cod_data_source_block           I
_cod_original_cell_volume        1105.56(9)
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2243580