Noncentrosymmetric rare-earth copper gallium chalcogenides RE3CuGaCh7 (RE=La‒Nd; Ch=S, Se): An unexpected combination
Iyer, Abishek K.; Rudyk, Brent W.; Lin, Xinsong; Singh, Harpreet; Sharma, Arzoo Z.; Wiebe, Christopher R.; Mar, Arthur; Journal of Solid State Chemistry 229 (2015) 150–159; doi:10.1016/j.jssc.2015.05.016

data_1561847
_publ_section_title
;
 Noncentrosymmetric rare-earth copper gallium chalcogenides RE3CuGaCh7
 (RE=La--Nd; Ch=S, Se): An unexpected combination
;
_journal_name_full               'Journal of Solid State Chemistry'
_journal_page_first              150
_journal_page_last               159
_journal_paper_doi               10.1016/j.jssc.2015.05.016
_journal_volume                  229
_journal_year                    2015
_chemical_formula_structural     'Pr3 Cu Ga Se7'
_chemical_formula_sum            'Cu Ga Pr3 Se7'
_chemical_formula_weight         1108.71
_chemical_name_common
'praseodymium copper gallium selenide (3/1/1/7)'
_chemical_name_systematic
'praseodymium copper gallium selenide (3/1/1/7)'
_space_group_crystal_system      hexagonal
_space_group_IT_number           173
_space_group_name_Hall           'P 6c'
_space_group_name_H-M_alt        'P 63'
_atom_sites_solution_hydrogens   .
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_formula_units_Z            2
_cell_length_a                   10.4181(8)
_cell_length_b                   10.4181(8)
_cell_length_c                   6.3743(5)
_cell_measurement_reflns_used    6199
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      29.47
_cell_measurement_theta_min      3.91
_cell_volume                     599.16(8)
_computing_cell_refinement       'Bruker SAINT 8.34A (Bruker, 2013)'
_computing_data_collection       'Bruker APEX 2 (Bruker, 2008)'
_computing_data_reduction        'Bruker SAINT 8.34A'
_computing_molecular_graphics    'ATOMS 5.1 (Dowty, 1999)'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'Bruker SHELXTL'
_computing_structure_solution    'Bruker SHELXTL'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker PLATFORM/SMART APEX II CCD'
_diffrn_measurement_method       '\w and \f scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0492
_diffrn_reflns_av_unetI/netI     0.0314
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -15
_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            8787
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 1.000
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         33.098
_diffrn_reflns_theta_min         2.257
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    37.136
_exptl_absorpt_correction_T_max  0.3755
_exptl_absorpt_correction_T_min  0.1624
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   'Bruker SHELXTL (Sheldrick, 2013)'
_exptl_crystal_colour            grey
_exptl_crystal_density_diffrn    6.145
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       irregular
_exptl_crystal_F_000             950
_exptl_crystal_size_max          0.068
_exptl_crystal_size_mid          0.045
_exptl_crystal_size_min          0.043
_refine_diff_density_max         1.278
_refine_diff_density_min         -1.203
_refine_diff_density_rms         0.217
_refine_ls_abs_structure_details
;
 Flack x determined using 658 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons and Flack (2004), Acta Cryst. A60, s61).
;
_refine_ls_abs_structure_Flack   -0.06(4)
_refine_ls_extinction_coef       0.0025(4)
_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   1.110
_refine_ls_hydrogen_treatment    undef
_refine_ls_matrix_type           full
_refine_ls_number_parameters     41
_refine_ls_number_reflns         1526
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.110
_refine_ls_R_factor_all          0.0318
_refine_ls_R_factor_gt           0.0298
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0304P)^2^+4.4029P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0685
_refine_ls_wR_factor_ref         0.0694
_reflns_Friedel_coverage         0.860
_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     1.000
_reflns_number_gt                1474
_reflns_number_total             1526
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            JSSC-2015-229-150.cif
_cod_data_source_block           Pr3CuGaSe7
_cod_original_cell_volume        599.16(10)
_cod_database_code               1561847
_shelx_estimated_absorpt_t_min   0.187
_shelx_estimated_absorpt_t_max   0.298
_shelxl_version_number           2013-4
_shelx_res_checksum              83251
_shelx_hkl_checksum              87846