Silicatoniobate de Potassium, K~3~Nb~3~O~6~Si~2~O~7~
Jaulmes, S.; Launay, S.; Mahé, P.; Quarton, M.; Acta Crystallographica Section C 51 (1995) 794–796; doi:10.1107/S0108270194012114

data_2003439
_publ_section_title
;
 Silicatoniobate de Potassium, K~3~Nb~3~O~6~Si~2~O~7~
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_journal_issue                   5
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              794
_journal_page_last               796
_journal_paper_doi               10.1107/S0108270194012114
_journal_volume                  51
_journal_year                    1995
_chemical_formula_sum            'K3 Nb3 O13 Si2'
_chemical_formula_weight         660.18
_space_group_IT_number           190
_symmetry_cell_setting           hexagonal
_symmetry_space_group_name_Hall  'P -6c -2c'
_symmetry_space_group_name_H-M   'P -6 2 c'
_atom_type_scat_source           IntTabIV
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_formula_units_Z            2
_cell_length_a                   9.012(1)
_cell_length_b                   9.012(1)
_cell_length_c                   8.027(1)
_cell_measurement_reflns_used    18
_cell_measurement_temperature    293
_cell_measurement_theta_max      10.2
_cell_measurement_theta_min      4.5
_cell_volume                     564.58(11)
_computing_molecular_graphics    'MOLVIEW (Cense, 1990)'
_computing_publication_material  'ORFFE (Busing, Martin & Levy, 1964)'
_computing_structure_refinement
;
ORXFLS (Busing, 1971) modifi\'e par P. Laruelle
;
_computing_structure_solution    'MULTAN80 (Main et al., 1980)'
_diffrn_measurement_device       'Syntex-Nicolet P3F'
_diffrn_measurement_method       \q/2\q
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            348
_diffrn_reflns_theta_max         30
_diffrn_standards_decay_%        9
_diffrn_standards_interval_count 60
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    4.254
_exptl_absorpt_correction_T_max  0.851
_exptl_absorpt_correction_T_min  0.808
_exptl_absorpt_correction_type   'm\'ethode de Gauss (Busing & Levy, 1957)'
_exptl_crystal_colour            incolore
_exptl_crystal_density_diffrn    3.889
_exptl_crystal_density_meas      3.84(4)
_exptl_crystal_description       aiguille
_exptl_crystal_size_max          0.350
_exptl_crystal_size_mid          0.052
_exptl_crystal_size_min          0.038
_refine_diff_density_max         0.6
_refine_diff_density_min         -0.7
_refine_ls_extinction_coef       g=0.22E-6(7)
_refine_ls_extinction_method     'Becker & Coppens (1975)'
_refine_ls_goodness_of_fit_obs   0.8
_refine_ls_number_parameters     38
_refine_ls_number_reflns         210
_refine_ls_R_factor_obs          0.045
_refine_ls_shift/esd_max         0.00021
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     'w = 1/\s(F)'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_obs         0.061
_reflns_number_observed          210
_reflns_number_total             348
_reflns_observed_criterion       I>\s(I)
_cod_data_source_file            du1095.cif
_cod_data_source_block           du1095a
_cod_depositor_comments
;
The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value '1/\s(F)' was changed to 'calc'.
New tag '_refine_ls_weighting_details' was created. The value of the
new tag was set to 'w = 1/\s(F)'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
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_cod_original_cell_volume        564.6(2)
_cod_original_formula_sum        'K3 Nb3 O6 Si2 O7'
_cod_database_code               2003439