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#$Date: 2016-02-14 16:26:36 +0200 (Sun, 14 Feb 2016) $
#$Revision: 176435 $
#$URL: svn://www.crystallography.net/cod/cif/2/00/30/2003077.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/. The original data for this entry
# were provided by IUCr Journals, http://journals.iucr.org/.
#
# The file may be used within the scientific community so long as
# proper attribution is given to the journal article from which the
# data were obtained.
#
data_2003077
loop_
_publ_author_name
'Ling, C. D.'
'Schmid, S.'
'Withers, R. L.'
'Thompson, J. G.'
'Ishizawa, N.'
'Kishimoto, S'
_publ_section_title
;
 Solution and refinement of the crystal structure of Bi₇Ta₃O₁₈
;
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              157
_journal_page_last               164
_journal_paper_doi               10.1107/S0108768198011148
_journal_volume                  55
_journal_year                    1999
_chemical_formula_sum            'Bi7 O18 Ta3'
_chemical_formula_weight         2293.71
_chemical_name_systematic
;
bismuth tantalum oxide
;
_space_group_IT_number           12
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2y'
_symmetry_space_group_name_H-M   'C 1 2/m 1'
_cell_angle_alpha                90.0
_cell_angle_beta                 109.2375(11)
_cell_angle_gamma                90.0
_cell_formula_units_Z            4
_cell_length_a                   34.0084(9)
_cell_length_b                   7.6069(2)
_cell_length_c                   6.63644(17)
_cell_measurement_temperature    293
_cell_volume                     1620.97(7)
_computing_structure_refinement  GSAS
_diffrn_ambient_temperature      293
_diffrn_measurement_device       '3He gas and ZnS scintillation counters'
_diffrn_measurement_method       time-of-flight
_diffrn_radiation_probe          neutron
_diffrn_radiation_source         spallation
_diffrn_radiation_type           neutron
_refine_ls_goodness_of_fit_all   5.41
_refine_ls_number_parameters     116
_cod_data_source_file            os0006.cif
_cod_data_source_block           pow
_cod_original_cell_volume        1620.94(7)
_cod_original_sg_symbol_H-M      'C 2/m'
_cod_original_formula_sum        'Bi7 Ta3 O18'
_cod_database_code               2003077
loop_
_symmetry_equiv_pos_as_xyz
+x,+y,+z
-x,+y,-z
-x,-y,-z
+x,-y,+z
+x+1/2,+y+1/2,+z
-x+1/2,+y+1/2,-z
-x+1/2,-y+1/2,-z
+x+1/2,-y+1/2,+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
Bi1 .24592(12) .5 .4693(6) .0114(7) Uiso 1.0
Bi2 .14509(7) .2522(4) .4641(3) .0154(5) Uiso 1.0
Bi3 .14788(9) .5 .9794(5) .0019(6) Uiso 1.0
Ta4 .05535(7) .2490(3) .9919(4) .0011(4) Uiso 1.0
Bi5 .04985(10) .5 .4544(6) .0234(11) Uiso 1.0
Ta6 .25 .25 .0 .0032(8) Uiso 1.0
Bi7 .16126(10) .0 .0205(5) .0119(6) Uiso 1.0
Bi8 .05314(9) .0 .5117(5) .0043(6) Uiso 1.0
O9 .07053(12) .5 .0872(5) .0016(8) Uiso 1.0
O10 .11913(9) .2017(4) .0979(5) .0085(7) Uiso 1.0
O11 .04957(9) .2973(4) .7019(4) .0064(6) Uiso 1.0
O12 .07096(9) .2109(5) .3232(5) .0106(7) Uiso 1.0
O13 .04746(14) .0 .9260(7) .0098(10) Uiso 1.0
O14 .0 .2889(5) .0 .0026(7) Uiso 1.0
O15 .23936(13) .2937(7) .6883(7) .0436(13) Uiso 1.0
O16 .23930(15) .0 .9454(8) .0140(10) Uiso 1.0
O17 .16979(15) .5 .3363(8) .0131(10) Uiso 1.0
O18 .18926(11) .2898(5) .9466(6) .0223(9) Uiso 1.0
O19 .11791(16) .0 .6697(8) .0206(12) Uiso 1.0
O20 .11376(13) .5 .5550(7) .0035(8) Uiso 1.0
O21 .18336(13) .0 .3733(7) .0086(8) Uiso 1.0
loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
Bi ? -9.511 4.206 Int._Tables_Vol_IV_Tables_2.2B_and_2.3.1
Ta ? -3.946 10.597 Int._Tables_Vol_IV_Tables_2.2B_and_2.3.1
O ? .015015 .012024 Int._Tables_Vol_IV_Tables_2.2B_and_2.3.1
