Synchrotron-radiation study of the two-leg spin-ladder (VO)~2~P~2~O~7~ at 120K
Geupel, Sandra; Pilz, Katrin; van Smaalen, Sander; Büllesfeld, Frank; Prokofiev, Andrei; Assmus, Wolf; Acta Crystallographica Section C 58 (2002) i9–i13; doi:10.1107/S0108270101017553

data_2012418
_publ_section_title
;
 Synchrotron-radiation study of the two-leg spin-ladder (VO)~2~P~2~O~7~
 at 120K
;
_journal_issue                   1
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              i9
_journal_page_last               i13
_journal_paper_doi               10.1107/S0108270101017553
_journal_volume                  58
_journal_year                    2002
_chemical_formula_iupac          '(V O)2 P2 O7'
_chemical_formula_moiety         '(V O 2+)2, (P2 O7 4-)'
_chemical_formula_structural     '(V O)2 P2 O7'
_chemical_formula_sum            'O9 P2 V2'
_chemical_formula_weight         307.82
_chemical_name_common            'Vanadyl pyrophosphate'
_chemical_name_systematic        'Oxovanadium(IV) diphosphate'
_space_group_IT_number           29
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2ac'
_symmetry_space_group_name_H-M   'P c a 21'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   7.7004(4)
_cell_length_b                   9.5777(5)
_cell_length_c                   16.5825(8)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      22.5
_cell_measurement_theta_min      16.1
_cell_volume                     1222.99(11)
_computing_cell_refinement
'MACH3 in CAD-4 UNIX Software (Enraf-Nonius, 1998)'
_computing_data_collection       'SMART (Siemens, 1996)'
_computing_data_reduction        'SAINT (Siemens, 1996)'
_computing_molecular_graphics
;
DIAMOND (Brandenburg, 1999) and ORTEP-3 (Farrugia, 1997)
;
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      120(2)
_diffrn_detector_area_resol_mean
;
  number of pixels: 1024 x 1024 (512 x 512 in binning mode), pixel size:
  60 \mm x 60 \mm
;
_diffrn_measured_fraction_theta_full .957
_diffrn_measured_fraction_theta_max .957
_diffrn_measurement_device_type
;
  Huber four-circle Kappa diffractometer with Siemens SMART CCD area detector
  and Oxford Cryostream Cooler
;
_diffrn_measurement_method       '\w and \f'
_diffrn_radiation_monochromator  'Si (111)'
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     .70843
_diffrn_reflns_av_R_equivalents  .0600
_diffrn_reflns_av_sigmaI/netI    .0551
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            11910
_diffrn_reflns_reduction_process
;
  Overloaded reflections were omitted in the data reduction process.
;
_diffrn_reflns_theta_full        30.40
_diffrn_reflns_theta_max         30.40
_diffrn_reflns_theta_min         2.12
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count none
_diffrn_standards_interval_time  none
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    3.548
_exptl_absorpt_correction_T_max  .950
_exptl_absorpt_correction_T_min  .804
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            'dark green'
_exptl_crystal_density_diffrn    3.344
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'rectangular prism'
_exptl_crystal_F_000             1184
_exptl_crystal_size_max          .100
_exptl_crystal_size_mid          .040
_exptl_crystal_size_min          .030
_refine_diff_density_max         .813
_refine_diff_density_min         -.669
_refine_ls_abs_structure_details 'Flack (1983), 1303 Friedel pairs'
_refine_ls_abs_structure_Flack   .00(13)
_refine_ls_extinction_coef       .0165(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 1997)'
_refine_ls_goodness_of_fit_ref   .877
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_constraints    0
_refine_ls_number_parameters     237
_refine_ls_number_reflns         3149
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      .877
_refine_ls_R_factor_all          .0352
_refine_ls_R_factor_gt           .0306
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         .000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0302P)^2^] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          .0675
_refine_ls_wR_factor_ref         .0684
_reflns_number_gt                2452
_reflns_number_total             3149
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            br1349.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value 'not measured' was changed to '?' -
the value is undefined or not given.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_database_code               2012418
_cod_database_fobs_code          2012418