α- and β-A2Hg3M2S8 (A = K, Rb; M = Ge, Sn): Polar Quaternary Chalcogenides with Strong Nonlinear Optical Response
J.-H. Liao; G. M. Marking; K. F. Hsu; Y. Matsushita; M. D. Ewbank; R. Borwick; P. Cunningham; M. J. Rosker; M. G. Kanatzidis; Journal of the American Chemical Society 125 (2003) 9484–9493; doi:10.1021/ja034121l

data_4114009
_publ_section_title
;
 \a- and \b-A2Hg3M2S8 (A = K, Rb; M = Ge, Sn): Polar Quaternary
 Chalcogenides with Strong Nonlinear Optical Response
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              9484
_journal_page_last               9493
_journal_paper_doi               10.1021/ja034121l
_journal_volume                  125
_journal_year                    2003
_chemical_formula_moiety         'K2 Hg3 Ge2 S8'
_chemical_formula_sum            'Ge2 Hg3 K2 S8'
_chemical_formula_weight         1081.63
_chemical_name_systematic
;
 potassium mercury germanium sulfide (2/3/2/8)
;
_space_group_IT_number           41
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'A 2 -2ab'
_symmetry_space_group_name_H-M   'A b a 2'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   19.082(8)
_cell_length_b                   9.551(4)
_cell_length_c                   8.2871(8)
_cell_measurement_reflns_used    1464
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.767
_cell_measurement_theta_min      3.254
_cell_volume                     1510.3(9)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.878
_diffrn_measured_fraction_theta_max 0.878
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0713
_diffrn_reflns_av_sigmaI/netI    0.0718
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            2904
_diffrn_reflns_theta_full        28.58
_diffrn_reflns_theta_max         28.58
_diffrn_reflns_theta_min         3.43
_exptl_absorpt_coefficient_mu    71.889
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.3635
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details
;
 The absorption correction was based on 2703 symmetry-equivalent reflections
 using the SADABS program. Sheldric, G. M. (1996). SADABS. Bruker Area
Detector
 Absorption Correction Software. University of Gottingen, Germany.
;
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    9.514
_exptl_crystal_description       chunk
_exptl_crystal_F_000             3760
_exptl_crystal_size_max          0.14
_exptl_crystal_size_mid          0.14
_exptl_crystal_size_min          0.02
_refine_diff_density_max         6.853
_refine_diff_density_min         -3.967
_refine_diff_density_rms         0.758
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.01(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.132
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     69
_refine_ls_number_reflns         1510
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.132
_refine_ls_R_factor_all          0.0881
_refine_ls_R_factor_gt           0.0751
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0942P)^2^+265.4150P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1876
_refine_ls_wR_factor_ref         0.1953
_reflns_number_gt                1272
_reflns_number_total             1510
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja034121lsi20030416_055253_1.cif
_cod_data_source_block           K2Hg3Ge2S8(1)
_cod_original_cell_volume        1510.3(5)
_cod_database_code               4114009