A Transition from Localized to Strongly Correlated Electron Behavior and Mixed Valence Driven by Physical or Chemical Pressure in ACo2As2 (A = Eu and Ca).
Tan, Xiaoyan; Fabbris, Gilberto; Haskel, Daniel; Yaroslavtsev, Alexander A.; Cao, Huibo; Thompson, Corey M.; Kovnir, Kirill; Menushenkov, Alexey P.; Chernikov, Roman V.; Garlea, V. Ovidiu; Shatruk, Michael; Journal of the American Chemical Society 138 (2016) 2724–2731; doi:10.1021/jacs.5b12659

data_4124924
_publ_section_title
;
 A Transition from Localized to Strongly Correlated Electron Behavior and
 Mixed Valence Driven by Physical or Chemical Pressure in ACo2As2 (A = Eu
 and Ca).
;
_journal_issue                   8
_journal_name_full               'Journal of the American Chemical Society'
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_journal_page_last               2731
_journal_paper_doi               10.1021/jacs.5b12659
_journal_volume                  138
_journal_year                    2016
_chemical_formula_sum            'As2 Ca0.9 Co1.906 Eu0.1'
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_space_group_name_Hall           '-I 4 2'
_space_group_name_H-M_alt        'I 4/m m m'
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_cell_measurement_theta_min      3.93
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_diffrn_measurement_device_type  'Bruker APEX II CCD area-detector'
_diffrn_measurement_method       'profile data from \w scans'
_diffrn_radiation_type           MoK\a
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_diffrn_reflns_point_group_measured_fraction_full 1.000
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_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2014/7 (Sheldrick 2014)'
_refine_ls_goodness_of_fit_ref   1.200
_refine_ls_hydrogen_treatment    undef
_refine_ls_matrix_type           full
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_refine_ls_R_factor_all          0.0260
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
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'w=1/[\s^2^(Fo^2^)+(0.0328P)^2^+0.1905P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_reflns_number_total             235
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja5b12659_si_004.cif
_cod_data_source_block           shelx
_cod_depositor_comments
'Adding full bibliography for 4124924--4124927.cif.'
_cod_original_cell_volume        165.781(19)
_cod_original_formula_sum        'As2 Ca0.90 Co1.906 Eu0.10'
_cod_database_code               4124924
_shelxl_version_number           2014-3
_shelx_res_checksum              39701
_shelx_hkl_checksum              16594