First-Order Phase Transition in BaNi2Ge2 and the Influence of the Valence Electron Count on Distortion of the ThCr2Si2 Structure Type.
Hlukhyy, Viktor; Trots, Dmytro; Fässler, Thomas F; Inorganic chemistry 56 (2017) 1173–1185; doi:10.1021/acs.inorgchem.6b02190

data_4345405
_publ_section_title
;
 First-Order Phase Transition in BaNi2Ge2 and the Influence of the Valence
 Electron Count on Distortion of the ThCr2Si2 Structure Type.
;
_journal_issue                   3
_journal_name_full               'Inorganic chemistry'
_journal_page_first              1173
_journal_page_last               1185
_journal_paper_doi               10.1021/acs.inorgchem.6b02190
_journal_volume                  56
_journal_year                    2017
_chemical_formula_sum            'Ba Ge2 Ni2'
_chemical_formula_weight         399.94
_space_group_crystal_system      orthorhombic
_space_group_IT_number           62
_space_group_name_Hall           '-P 2ac 2n'
_space_group_name_H-M_alt        'P n m a'
_symmetry_space_group_name_Hall  '-P 2ac 2n'
_symmetry_space_group_name_H-M   'P n m a'
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   8.3901(3)
_cell_length_b                   11.3249(4)
_cell_length_c                   4.2950(2)
_cell_measurement_reflns_used    1121
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      25
_cell_measurement_theta_min      3
_cell_volume                     408.10(3)
_computing_cell_refinement       Fullprof
_computing_data_collection       'XArea (Stoe, 2004)'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXS-2014/7 (Sheldrick, 2014)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'STOE IPDS 2T imaging plate diffractomter'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0990
_diffrn_reflns_av_unetI/netI     0.0335
_diffrn_reflns_Laue_measured_fraction_full 0.997
_diffrn_reflns_Laue_measured_fraction_max 0.998
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       5
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            5955
_diffrn_reflns_point_group_measured_fraction_full 0.997
_diffrn_reflns_point_group_measured_fraction_max 0.998
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.499
_diffrn_reflns_theta_min         4.859
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    32.884
_exptl_absorpt_correction_T_max  0.1185
_exptl_absorpt_correction_T_min  0.0244
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details
'STOE X-RED (crystal shape optimized with STOE X-SHAPE)'
_exptl_crystal_colour            'metallic silver'
_exptl_crystal_density_diffrn    6.509
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             704
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.04
_exptl_crystal_size_min          0.01
_refine_diff_density_max         1.516
_refine_diff_density_min         -1.369
_refine_diff_density_rms         0.338
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.136
_refine_ls_hydrogen_treatment    undef
_refine_ls_matrix_type           full
_refine_ls_number_parameters     25
_refine_ls_number_reflns         492
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.136
_refine_ls_R_factor_all          0.0403
_refine_ls_R_factor_gt           0.0351
_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^)+(0.0346P)^2^+8.9885P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0845
_refine_ls_wR_factor_ref         0.0872
_reflns_Friedel_coverage         0.000
_reflns_number_gt                456
_reflns_number_total             492
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ic6b02190_si_002.cif
_cod_data_source_block           LT-BaNi2Ge2
_cod_database_code               4345405
_publcif_datablock.id            {daba9faa-6c6a-4b63-83ea-37b3aad1f596}
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              57142
_shelx_hkl_checksum              46954
_publcif_info_exptl_table_max_cols 4
_publcif_info_exptl_table_use_headnotes n