data_2102118
_publ_section_title
;
 Ab initio structure determination and Rietveld refinement of a
 high-temperature phase of zirconium hydrogen phosphate and a new
 polymorph of zirconium pyrophosphate from in situ
 temperature-resolved powder diffraction data
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              618
_journal_page_last               625
_journal_paper_doi               10.1107/S0108768100003645
_journal_volume                  56
_journal_year                    2000
_chemical_formula_structural     ZrP~2~O~7~
_chemical_formula_sum            'O7 P2 Zr'
_chemical_formula_weight         265.16
_chemical_name_common            'Zirconium Pyrophosphate'
_chemical_name_systematic        'Zirconium Pyrophosphate'
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2 2n'
_symmetry_space_group_name_H-M   'P n n m'
_cell_angle_alpha                90.0
_cell_angle_beta                 90.0
_cell_angle_gamma                90.0
_cell_formula_units_Z            2
_cell_length_a                   8.3127(4)
_cell_length_b                   6.6389(4)
_cell_length_c                   5.3407(3)
_cell_measurement_temperature    778
_cell_volume                     294.74(3)
_computing_structure_refinement  GSAS
_diffrn_measurement_device_type  'NSLS beamline X7B, BNL'
_diffrn_radiation_source         'X-ray synchrotron'
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     .9336
_diffrn_reflns_number            202
_exptl_absorpt_coefficient_mu    1.20
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            white
_exptl_crystal_density_diffrn    3.01
_refine_ls_goodness_of_fit_all   2.02
_refine_ls_number_parameters     40
_refine_ls_number_reflns         202
_refine_ls_number_restraints     0
_refine_ls_shift/esd_mean        .01
_refine_ls_shift/su_max          .01
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_scheme      sigma
_reflns_number_gt                202
_reflns_number_total             202
_[local]_cod_data_source_file    os0045.cif
_cod_database_code               2102118
loop_
_symmetry_equiv_pos_as_xyz
+x,+y,+z
-x+1/2,+y+1/2,+z+1/2
+x+1/2,-y+1/2,+z+1/2
-x,-y,+z
-x,-y,-z
+x+1/2,-y+1/2,-z+1/2
-x+1/2,+y+1/2,-z+1/2
+x,+y,-z
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_thermal_displace_type
_atom_site_occupancy
Zr .0 .5 .0 .0370(7) Uiso 1.0
P .3908(6) .3129(7) .0 .047(2) Uiso 1.0
O1 .4335(7) .2019(9) .7710(11) .058(3) Uiso 1.0
O2 .2222(14) .3908(12) .0 .084(4) Uiso 1.0
O3 .0 .0 .5 .107(5) Uiso 1.0
loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
O O .0106 .0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
P P .1023 .0942 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
Zr Zr -2.9673 .5597 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
