Pressure-induced coherent sliding-layer transition in the excitonic insulator Ta<sub>2</sub>NiSe<sub>5</sub>.
Nakano, Akitoshi; Sugawara, Kento; Tamura, Shinya; Katayama, Naoyuki; Matsubayashi, Kazuyuki; Okada, Taku; Uwatoko, Yoshiya; Munakata, Kouji; Nakao, Akiko; Sagayama, Hajime; Kumai, Reiji; Sugimoto, Kunihisa; Maejima, Naoyuki; Machida, Akihiko; Watanuki, Tetsu; Sawa, Hiroshi; IUCrJ 5 (2018) 158–165; doi:10.1107/S2052252517018334

data_1556756
_publ_section_title
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 Pressure-induced coherent sliding-layer transition in the excitonic
 insulator Ta<sub>2</sub>NiSe<sub>5</sub>.
;
_journal_issue                   'Pt 2'
_journal_name_full               IUCrJ
_journal_page_first              158
_journal_page_last               165
_journal_paper_doi               10.1107/S2052252517018334
_journal_volume                  5
_journal_year                    2018
_chemical_formula_sum            'Ni Se5 Ta2'
_chemical_formula_weight         815.41
_space_group_IT_number           63
_space_group_name_Hall           '-C 2c 2'
_space_group_name_H-M_alt        'C m c m'
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_H-M   'C m c 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            4
_cell_length_a                   3.50290(10)
_cell_length_b                   12.8699(5)
_cell_length_c                   15.6768(8)
_cell_measurement_reflns_used    34120
_cell_measurement_temperature    400(2)
_cell_measurement_theta_max      20.380
_cell_measurement_theta_min      1.02
_cell_volume                     706.74(5)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      400(2)
_diffrn_measured_fraction_theta_full 0.968
_diffrn_measured_fraction_theta_max 0.968
_diffrn_measurement_device_type  IPDSC-Q
_diffrn_measurement_method       oscillation
_diffrn_radiation_monochromator  silicon
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.27865
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0291
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       32
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       38
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            3100
_diffrn_reflns_theta_full        20.38
_diffrn_reflns_theta_max         20.38
_diffrn_reflns_theta_min         1.02
_diffrn_standards_number         3272
_exptl_absorpt_coefficient_mu    4.361
_exptl_absorpt_correction_type   empirical
_exptl_crystal_colour            silver
_exptl_crystal_density_diffrn    7.663
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             1376
_exptl_crystal_size_max          0.90
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.10
_refine_diff_density_max         2.739
_refine_diff_density_min         -2.617
_refine_diff_density_rms         0.653
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.147
_refine_ls_matrix_type           full
_refine_ls_number_parameters     27
_refine_ls_number_reflns         3100
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.147
_refine_ls_R_factor_all          0.0238
_refine_ls_R_factor_gt           0.0197
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0206P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0519
_refine_ls_wR_factor_ref         0.0530
_reflns_number_gt                2745
_reflns_number_total             3100
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            fc5022.cif
_cod_data_source_block           Ta2NiSe5_0GPa_400K
_cod_depositor_comments
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The following automatic conversions were performed:

data item '_symmetry_cell_setting' value 'Orthorhombic' was changed
to 'orthorhombic' in accordance with the
/home/saulius/struct/COD-crude-data/automatic-downloads/DataCite-retrospective/IUCr/depositions/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 last updated on
2011-04-26.

Automatic conversion script
Id: cif_fix_values 7556 2019-12-06 15:28:31Z antanas 
;
_cod_original_sg_symbol_H-M      Cmcm
_cod_database_code               1556756