β-K~2~Cr~2~O~7~
Krivovichev, Sergey V.; Kir'yanova, Elena V.; Filatov, Stanislav K.; Burns, Peter C.; Acta Crystallographica Section C 56 (2000) 629–630; doi:10.1107/S0108270100003917

data_2010992
_publ_section_title
;
 \b-K~2~Cr~2~O~7~
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              629
_journal_page_last               630
_journal_paper_doi               10.1107/S0108270100003917
_journal_volume                  56
_journal_year                    2000
_chemical_formula_moiety         'K2 Cr2 O7'
_chemical_formula_sum            'Cr2 K2 O7'
_chemical_formula_weight         294.20
_chemical_name_common            'dipotassium dichromate'
_chemical_name_systematic        'dipotassium dichromate'
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_cell_angle_alpha                90.00
_cell_angle_beta                 91.923(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   13.0339(17)
_cell_length_b                   7.3750(10)
_cell_length_c                   7.4672(10)
_cell_measurement_reflns_used    523
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      23
_cell_measurement_theta_min      3
_cell_volume                     717.38(17)
_computing_cell_refinement       'SAINT-NT (Bruker, 1998)'
_computing_data_collection       'SMART-NT (Bruker, 1998)'
_computing_data_reduction        SAINT-NT
_computing_molecular_graphics    'CRYSTALMAKER (Palmer, 1999)'
_computing_publication_material  SHELXTL
_computing_structure_refinement  SHELXTL
_computing_structure_solution    'SHELXTL (Bruker, 1997)'
_database_code_amcsd             0010323
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full .911
_diffrn_measured_fraction_theta_max .911
_diffrn_measurement_device_type
'Bruker PLATFORM with a SMART CCD area detector'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     .71073
_diffrn_reflns_av_R_equivalents  .045
_diffrn_reflns_av_sigmaI/netI    .029
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -6
_diffrn_reflns_number            1779
_diffrn_reflns_theta_full        28.26
_diffrn_reflns_theta_max         28.26
_diffrn_reflns_theta_min         3.13
_diffrn_standards_decay_%        none
_diffrn_standards_interval_time  100
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    4.175
_exptl_absorpt_correction_T_max  .686
_exptl_absorpt_correction_T_min  .317
_exptl_absorpt_correction_type   \y-scan
_exptl_absorpt_process_details   'empirical (SAINT-NT; Bruker, 1998)'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    2.724
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             568
_exptl_crystal_size_max          .46
_exptl_crystal_size_mid          .24
_exptl_crystal_size_min          .09
_refine_diff_density_max         .495
_refine_diff_density_min         -.516
_refine_ls_extinction_coef       .0074(11)
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 1997)'
_refine_ls_goodness_of_fit_ref   1.107
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     52
_refine_ls_number_reflns         798
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.107
_refine_ls_R_factor_all          .032
_refine_ls_R_factor_gt           .029
_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^)+(0.0513P)^2^+0.5383P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         .084
_reflns_number_gt                718
_reflns_number_total             798
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            fg1580.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               2010992
_cod_database_fobs_code          2010992
_amcsd_formula_title             K2Cr2O7