Band gap tuning from an indirect EuGa2S4 to a direct EuZnGeS4 semiconductor: syntheses, crystal and electronic structures, and optical properties
Chi, Yang; Guo, Sheng-Ping; Xue, Huai-Guo; RSC Adv. 7 (2017) 5039–; doi:10.1039/C6RA25283D

data_7227463
_publ_section_title
;
 Band gap tuning from an indirect EuGa2S4 to a direct EuZnGeS4
 semiconductor: syntheses, crystal and electronic structures, and optical
 properties
;
_journal_issue                   9
_journal_name_full               'RSC Adv.'
_journal_page_first              5039
_journal_paper_doi               10.1039/C6RA25283D
_journal_volume                  7
_journal_year                    2017
_chemical_formula_moiety         'Eu Ge S4 Zn'
_chemical_formula_sum            'Eu Ge S4 Zn'
_chemical_formula_weight         418.16
_chemical_name_systematic
;
 ? 
;
_space_group_crystal_system      orthorhombic
_space_group_IT_number           70
_space_group_name_Hall           '-F 2uv 2vw'
_space_group_name_H-M_alt        'F d d d'
_symmetry_space_group_name_Hall  '-F 2uv 2vw'
_symmetry_space_group_name_H-M   'F d d d :2'
_audit_creation_date             2016-07-16
_audit_creation_method
;
Olex2 1.2-beta
(compiled 2015.08.17 svn.r3210 for OlexSys, GUI svn.r5083)
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            32
_cell_length_a                   20.398(6)
_cell_length_b                   20.682(6)
_cell_length_c                   12.234(4)
_cell_measurement_reflns_used    2852
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      27.4309
_cell_measurement_theta_min      3.5668
_cell_volume                     5161(3)
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2015)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296.15
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'Bruker P4'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0283
_diffrn_reflns_av_unetI/netI     0.0249
_diffrn_reflns_Laue_measured_fraction_full 0.993
_diffrn_reflns_Laue_measured_fraction_max 0.993
_diffrn_reflns_limit_h_max       24
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -24
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            5315
_diffrn_reflns_point_group_measured_fraction_full 0.993
_diffrn_reflns_point_group_measured_fraction_max 0.993
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.498
_diffrn_reflns_theta_min         2.177
_exptl_absorpt_coefficient_mu    19.076
_exptl_absorpt_correction_type   none
_exptl_crystal_density_diffrn    4.305
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             6048
_exptl_crystal_size_max          0.13
_exptl_crystal_size_mid          0.12
_exptl_crystal_size_min          0.11
_refine_diff_density_max         2.571
_refine_diff_density_min         -1.815
_refine_diff_density_rms         0.403
_refine_ls_extinction_coef       0.000173(11)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2016/3 (Sheldrick 2016)'
_refine_ls_goodness_of_fit_ref   1.129
_refine_ls_hydrogen_treatment    undef
_refine_ls_matrix_type           full
_refine_ls_number_parameters     67
_refine_ls_number_reflns         1203
_refine_ls_number_restraints     12
_refine_ls_restrained_S_all      1.155
_refine_ls_R_factor_all          0.0553
_refine_ls_R_factor_gt           0.0483
_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^)+(0.0303P)^2^+1871.4999P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1245
_refine_ls_wR_factor_ref         0.1279
_reflns_Friedel_coverage         0.000
_reflns_number_gt                926
_reflns_number_total             1203
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c6ra25283d4.cif
_cod_data_source_block           a
_cod_database_code               7227463
_shelx_estimated_absorpt_t_max   0.228
_shelx_estimated_absorpt_t_min   0.191
_olex2_refinement_description
;
1. Uiso/Uaniso restraints and constraints
Uanis(S3) \\sim Ueq, Uanis(S4) \\sim Ueq: with sigma of 0.001 and sigma for
terminal atoms of 0.002
;
_shelx_shelxl_version_number     2016/3
_olex2_submission_special_instructions 'No special instructions were received'