Crystal structures of nickel germanium selenide, Ni~5.45~GeSe~2~, and nickel germanium telluride, Ni~5.45~GeTe~2~
Deiseroth, Hans-Jörg; Spirovski, Filip; Reiner, Christof; Schlosser, Marc; Zeitschrift für Kristallographie - New Crystal Structures 222 (2007) 171–172; doi:

data_8102973
_publ_section_title
;
Crystal structures of nickel germanium selenide, Ni~5.45~GeSe~2~, 
and nickel germanium telluride, Ni~5.45~GeTe~2~
;
_journal_issue                   3
_journal_name_full
'Zeitschrift f\"ur Kristallographie - New Crystal Structures'
_journal_page_first              171
_journal_page_last               172
_journal_volume                  222
_journal_year                    2007
_chemical_formula_structural     Ni5.45GeSe2
_chemical_formula_sum            'Ge Ni5 Se2'
_chemical_formula_weight         524.06
_chemical_name_systematic
;
 nickel germanium sellenide
;
_space_group_IT_number           139
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  '-I 4 2'
_symmetry_space_group_name_H-M   'I 4/m m m'
_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            2
_cell_length_a                   3.6117(4)
_cell_length_b                   3.6117(4)
_cell_length_c                   18.281(3)
_cell_measurement_reflns_used    1767
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      31.7
_cell_measurement_theta_min      4.5
_cell_volume                     238.46(5)
_computing_cell_refinement       STOE-IPDS
_computing_data_collection       'STOE-IPDS (STOE & Cie, 1999)'
_computing_data_reduction        'SHELXL-97 (Sheldrick, 1997)'
_computing_molecular_graphics    'DIAMOND 2.1e (Brandenburg, 2001)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXL-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.994
_diffrn_measured_fraction_theta_max 0.994
_diffrn_measurement_device_type  'Stoe IPDS 1'
_diffrn_measurement_method       phi
_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  0.1530
_diffrn_reflns_av_sigmaI/netI    0.0585
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -5
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            1613
_diffrn_reflns_theta_full        31.69
_diffrn_reflns_theta_max         31.69
_diffrn_reflns_theta_min         4.46
_exptl_absorpt_coefficient_mu    40.636
_exptl_absorpt_correction_T_max  0.4258
_exptl_absorpt_correction_T_min  0.0034
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details
;
Prior the numerical absorption correction, the
crystal shape and dimensions were optimized on
the basis of equivalent reflections by means of the
Stoe X-Shape program [13].
;
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    7.299
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             480
_exptl_crystal_size_max          0.41
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.04
_refine_diff_density_max         3.573
_refine_diff_density_min         -6.452
_refine_diff_density_rms         1.820
_refine_ls_extinction_coef       0.097(8)
_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   1.275
_refine_ls_matrix_type           full
_refine_ls_number_parameters     17
_refine_ls_number_reflns         158
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.275
_refine_ls_R_factor_all          0.0531
_refine_ls_R_factor_gt           0.0510
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0375P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0714
_refine_ls_wR_factor_ref         0.0778
_reflns_number_gt                143
_reflns_number_total             158
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            409923.cff
_cod_data_source_block           ni5.45gese2
_cod_original_cell_volume        238.46(6)
_cod_original_sg_symbol_H-M      I4/mmm
_cod_database_code               8102973