Structure of the calcium pyrophosphate monohydrate phase (Ca~2~P~2~O~7~·H~2~O): towards understanding the dehydration process in calcium pyrophosphate hydrates
Gras, Pierre; Ratel-Ramond, Nicolas; Teychéné, Sébastien; Rey, Christian; Elkaim, Erik; Biscans, Béatrice; Sarda, Stéphanie; Combes, Christèle; Acta Crystallographica Section C 70 (2014) –; doi:10.1107/S2053229614017446

data_2019651
_publ_section_title
;
 Structure of the calcium pyrophosphate monohydrate phase
 (Ca~2~P~2~O~7~&#x00B7;H~2~O): towards understanding the dehydration
 process in calcium pyrophosphate hydrates
;
_journal_coeditor_code           KU3136
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first
;
;
_journal_paper_doi               10.1107/S2053229614017446
_journal_volume                  70
_journal_year                    2014
_chemical_formula_iupac          'Ca2 P2 O7 , H2 O'
_chemical_formula_moiety         'O7 P2, H2 O, 2(Ca)'
_chemical_formula_sum            'Ca2 H2 O8 P2'
_chemical_formula_weight         272.12
_chemical_name_systematic
;
Calcium pyrophosphate monohydrate
;
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_cell_angle_beta                 114.4(4)
_cell_angle_gamma                90
_cell_formula_units_Z            4
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_cell_length_b                   6.97(5)
_cell_length_c                   10.77(10)
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_cell_measurement_theta_max      27.8057
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_computing_data_reduction        'SORTAV (Blessing, 1995)'
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_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      180(2)
_diffrn_measured_fraction_theta_full 0.99
_diffrn_measured_fraction_theta_max 0.987
_diffrn_measurement_device_type
'Bruker Kappa APEXII diffractometer with Quasar CCD area-detector'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  'multilayer optics'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0585
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_diffrn_reflns_limit_k_max       8
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_exptl_absorpt_coefficient_mu    2.109
_exptl_absorpt_correction_T_max  0.9569
_exptl_absorpt_correction_T_min  0.6650
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Bruker, 2001)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.602
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             544
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_exptl_crystal_size_min          0.02
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_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0566P)^2^+4.0170P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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