Syntheses and crystal structures of the quaternary uranium lanthanide oxyselenides UYb2O2Se3 and U2Ln2O4Se3 (Ln=Pr, Sm, Gd)
Raw, Adam D.; Ibers, James A.; Journal of Solid State Chemistry 186 (2012) 177–181; doi:10.1016/j.jssc.2011.12.002

data_1563072
_publ_section_title
;
 Syntheses and crystal structures of the quaternary uranium lanthanide
 oxyselenides UYb2O2Se3 and U2Ln2O4Se3 (Ln=Pr, Sm, Gd)
;
_journal_name_full               'Journal of Solid State Chemistry'
_journal_page_first              177
_journal_page_last               181
_journal_paper_doi               10.1016/j.jssc.2011.12.002
_journal_volume                  186
_journal_year                    2012
_chemical_formula_moiety         'U2 Gd2 O4 Se3'
_chemical_formula_sum            'Gd2 O4 Se3 U2'
_chemical_formula_weight         1091.44
_chemical_name_common            'Uranium Gadolinium Oxyselenide'
_space_group_IT_number           55
_space_group_name_Hall           '-P 2 2ab'
_space_group_name_H-M_alt        'P b a m'
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_H-M   'P b a m'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   6.9724(4)
_cell_length_b                   14.8052(7)
_cell_length_c                   3.9678(2)
_cell_measurement_reflns_used    4530
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      28.46
_cell_measurement_theta_min      2.75
_cell_volume                     409.59(4)
_computing_cell_refinement       'SAINT (Bruker, 2009)'
_computing_data_collection       'SMART APEX CCD (Bruker 2003, 2009)'
_computing_data_reduction        'SAINT (Bruker, 2009)'
_computing_molecular_graphics    'CrystalMaker (Palmer, 2009)'
_computing_publication_material  'SHELXTL-97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.975
_diffrn_measured_fraction_theta_max 0.975
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \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  0.0345
_diffrn_reflns_av_sigmaI/netI    0.0193
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       5
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            4530
_diffrn_reflns_theta_full        28.46
_diffrn_reflns_theta_max         28.46
_diffrn_reflns_theta_min         2.75
_exptl_absorpt_coefficient_mu    68.684
_exptl_absorpt_correction_T_max  0.1306
_exptl_absorpt_correction_T_min  0.0226
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   'face indexed, SADABS (Sheldrick, 2008b)'
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    8.850
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'square plate'
_exptl_crystal_F_000             892
_exptl_crystal_size_max          0.23
_exptl_crystal_size_mid          0.22
_exptl_crystal_size_min          0.05
_refine_diff_density_max         1.687
_refine_diff_density_min         -2.336
_refine_diff_density_rms         0.365
_refine_ls_extinction_coef       0.0042(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.777
_refine_ls_matrix_type           full
_refine_ls_number_parameters     40
_refine_ls_number_reflns         580
_refine_ls_number_restraints     5
_refine_ls_restrained_S_all      1.769
_refine_ls_R_factor_all          0.0222
_refine_ls_R_factor_gt           0.0217
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
; calc 
 [1.00000+0.00000exp(0.00(sin\q/\l)^2^)]/ 
   [\s^2^(Fo^2^)+0.0000+0.0000*P+(0.0196P)^2^+0.0000sin\q/\l] 
 where P = 1.00000Fo^2^ + 0.00000Fc^2^ 
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0576
_refine_ls_wR_factor_ref         0.0577
_reflns_number_gt                565
_reflns_number_total             580
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            JSSC-2012-186-177.cif
_cod_data_source_block           U2Gd2O4Se3
_cod_original_sg_symbol_H-M      Pbam
_cod_database_code               1563072