#------------------------------------------------------------------------------
#$Date: 2016-02-14 16:26:36 +0200 (Sun, 14 Feb 2016) $
#$Revision: 176435 $
#$URL: svn://www.crystallography.net/cod/cif/2/00/28/2002893.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_2002893
loop_
_publ_author_name
'Thompson, John G'
'Withers, Ray L.'
'Melnitchenko, Alexandra'
'Palethorpe, Stephen R.'
_publ_section_title
;
 Cristobalite-Related Phases in the NaAlO₂--NaAlSiO₄ System. I. Two
 Tetragonal and Two Orthorhombic Structures
;
_journal_issue                   5
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              531
_journal_page_last               546
_journal_paper_doi               10.1107/S0108768197019927
_journal_volume                  54
_journal_year                    1998
_chemical_formula_sum            'Al1.75 Na1.75 O4 Si0.25'
_chemical_formula_weight         158.47
_chemical_name_systematic        ' ?'
_space_group_IT_number           61
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_cell_angle_alpha                90.0
_cell_angle_beta                 90.0
_cell_angle_gamma                90.0
_cell_formula_units_Z            8
_cell_length_a                   10.416(3)
_cell_length_b                   14.250(3)
_cell_length_c                   5.2038(9)
_cell_measurement_temperature    293
_cell_volume                     772.4(3)
_diffrn_ambient_temperature      293
_diffrn_measurement_device       'Siemens D-5000'
_diffrn_measurement_method       'profile data from theta/2theta scan'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.5418
_exptl_crystal_density_diffrn    2.726
_cod_data_source_file            ab0390.cif
_cod_data_source_block           Na1.75Al1.75Si0.25O4
_cod_original_cell_volume        772.40(10)
_cod_original_formula_sum        'Na1.75 Al1.75 Si0.25 O4'
_cod_database_code               2002893
loop_
_symmetry_equiv_pos_as_xyz
x,y,z
1/2-x,-y,1/2+z
-x,1/2+y,1/2-z
1/2+x,1/2-y,-z
-x,-y,-z
1/2+x,y,1/2-z
x,1/2-y,1/2+z
1/2-x,1/2+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_occupancy
_atom_site_type_symbol
M1 0.9800(10) 0.8120(10) 0.691(2) 0.875 0.035(3) Al
M1 0.9800(10) 0.8120(10) 0.691(2) 0.125 0.035(3) Si
M2 0.2710(10) 0.0610(10) 0.304(2) 0.875 0.035(3) Al
M2 0.2710(10) 0.0610(10) 0.304(2) 0.125 0.035(3) Si
Na1 0.484(5) 0.065(4) 0.703(12) 0.4375 0.093(6) Na
Na2 0.489(5) 0.049(4) 0.777(12) 0.4375 0.093(6) Na
Na3 0.745(4) 0.307(4) 0.161(9) 0.4375 0.093(6) Na
Na4 0.794(4) 0.322(3) 0.288(8) 0.4375 0.093(6) Na
O1 0.0750(10) 0.9070(10) 0.738(3) 1.0 0.046(4) O
O2 0.019(2) 0.7860(10) 0.372(3) 1.0 0.046(4) O
O3 0.238(2) 0.9600(10) 0.128(3) 1.0 0.046(4) O
O4 0.8270(10) 0.8450(10) 0.793(3) 1.0 0.046(4) O
