The α ↔ β phase transitions of Zn2P2O7 revisited: existence of an additional intermediate phase with an incommensurately modulated structure.
Stöger, Berthold; Weil, Matthias; Dušek, Michal; Acta Crystallographica, Section B: Structural Science, Crystal Engineering and Materials 70 (2014) 539–554; doi:10.1107/S205252061401049X

data_2310793
_publ_section_title
;
 The \a &#x2194; \b phase transitions of Zn2P2O7 revisited: existence of
 an additional intermediate phase with an incommensurately modulated
 structure.
;
_journal_coden_ASTM              ACSBDA
_journal_issue                   3
_journal_name_full
;
 Acta Crystallographica, Section B: Structural Science, Crystal Engineering
 and Materials
;
_journal_page_first              539
_journal_page_last               554
_journal_paper_doi               10.1107/S205252061401049X
_journal_volume                  70
_journal_year                    2014
_chemical_formula_sum            'O7 P2 Zn2'
_chemical_formula_weight         304.7
_chemical_name_common            'zinc pyrophosphate'
_chemical_name_systematic        'zinc(II) diphosphate(V)'
_space_group_IT_number           12
_space_group_ssg_name            C2/m(\a0\g)0s
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2y'
_symmetry_space_group_name_H-M   'C 1 2/m 1'
_cell_angle_alpha                90
_cell_angle_beta                 105.3906(15)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   6.6018(2)
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_cell_measurement_theta_max      45.3
_cell_measurement_theta_min      3.4
_cell_modulation_dimension       1
_cell_volume                     238.633(11)
_computing_cell_refinement       'SAINT-Plus (Bruker, 2012)'
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_computing_data_reduction        'SAINT-Plus (Bruker, 2012)'
_computing_molecular_graphics    'ATOMS (Dowty, 2006)'
_computing_structure_refinement  'JANA2006 (Pet\<r\'i\<cek, et al., 2006)'
_computing_structure_solution    'by isomorphous structure methods'
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_refine_diff_density_min         -0.78
_refine_ls_extinction_coef       2260(90)
_refine_ls_extinction_method
'B-C type 1 Gaussian isotropic (Becker & Coppens, 1974)'
_refine_ls_goodness_of_fit_gt    1.80
_refine_ls_goodness_of_fit_ref   1.22
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_refine_ls_number_reflns         5061
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0803
_refine_ls_R_factor_gt           0.0266
_refine_ls_shift/su_max          0.0431
_refine_ls_shift/su_mean         0.0036
_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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_publcif_datablock.id            {d06200ea-65bd-43dc-a379-278839bc3f40}