Crystal chemistry of transition metal diarsenates <i>M</i>~2~As~2~O~7~ (<i>M</i> = Mn, Co, Ni, Zn): variants of the thortveitite structure
Weil, Matthias; Stöger, Berthold; Acta Crystallographica Section B 66 (2010) 603–614; doi:10.1107/S0108768110040802

data_2104864
_publ_section_title
;
 Crystal chemistry of transition metal diarsenates <i>M</i>~2~As~2~O~7~
 (<i>M</i> = Mn, Co, Ni, Zn): variants of the thortveitite structure
;
_journal_coeditor_code           SN5100
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              603
_journal_page_last               614
_journal_paper_doi               10.1107/S0108768110040802
_journal_volume                  66
_journal_year                    2010
_chemical_formula_structural     'Zn2 As2 O7'
_chemical_formula_sum            'As2 O7 Zn2'
_chemical_formula_weight         392.6
_chemical_name_systematic
;
Zinc(II) diarsenate(V)
;
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_cell_measurement_theta_max      44.911
_cell_measurement_theta_min      3.5013
_cell_modulation_dimension       1
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_computing_cell_refinement       APEX2
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_computing_molecular_graphics    'ATOMS (Dowty, 2006)'
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'Jana2006 (Petricek, Dusek & Palatinus, 2006)'
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'Jana2006 (Petricek, Dusek & Palatinus, 2006)'
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_diffrn_ambient_temperature      240
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_diffrn_measured_fraction_theta_max 0.86
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'Bruker APEXII CCD'
_diffrn_radiation_monochromator  graphite
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_diffrn_radiation_type           'Mo K\a'
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_diffrn_reflns_av_R_equivalents  0.0479
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_exptl_crystal_description       plate
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_refine_ls_extinction_coef       192E1(5)
_refine_ls_extinction_method
'B-C type 1 Lorentzian isotropic (Becker & Coppens, 1974)'
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_refine_ls_shift/su_mean         0.0038
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     w=1/(\s^2^(F)+0.0001F^2^)
_refine_ls_weighting_scheme      sigma
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