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#$Date: 2010-06-10 18:11:07 +0300 (Thu, 10 Jun 2010) $
#$Revision: 1210 $
#$URL: file:///home/coder/svn-repositories/cod/cif/9/9005794.cif $
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#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/. The original data for this entry
# were provided the American Mineralogist Crystal Structure Database,
# http://rruff.geo.arizona.edu/AMS/amcsd.php
#
# 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_9005794
loop_
_publ_author_name
'Hazen, R. M.'
'Au, A. Y.'
_publ_section_title
;
 High-pressure crystal chemistry of phenakite (Be2SiO4)
 and bertrandite (Be4Si2O7(OH)2)
 Sample: P = 23 kbar
 Note: x-coordinate of O2 altered
;
_journal_name_full               'Physics and Chemistry of Minerals'
_journal_page_first              69
_journal_page_last               78
_journal_volume                  13
_journal_year                    1986
_chemical_formula_sum            'Be4 H2 O9 Si2'
_chemical_name_mineral           Bertrandite
_space_group_IT_number           36
_symmetry_space_group_name_Hall  'C 2c -2'
_symmetry_space_group_name_H-M   'C m c 21'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_length_a                   8.641
_cell_length_b                   15.051
_cell_length_c                   4.5338
_cell_volume                     589.646
_diffrn_ambient_pressure         2.3e+06
_exptl_crystal_density_diffrn    2.684
_[local]_cod_chemical_formula_sum_orig 'Be4 Si2 O9 H2'
_cod_database_code               9005794
_amcsd_database_code             AMCSD#0007315
loop_
_symmetry_equiv_pos_as_xyz
x,y,z
1/2+x,1/2+y,z
x,-y,1/2+z
1/2+x,1/2-y,1/2+z
-x,y,z
1/2-x,1/2+y,z
-x,-y,1/2+z
1/2-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
Be1 0.16790 0.05360 0.09400 0.00760
Be2 0.32460 0.22140 0.06100 0.00076
Si 0.32610 0.11350 0.65460 0.00659
O1 0.29390 0.12460 0.00000 0.01013
O2 0.20670 0.04380 0.49870 0.01267
O3 0.29480 0.20810 0.49040 0.01140
O4 0.00000 0.58210 0.58430 0.01140
O-H1 0.00000 0.76000 0.08260 0.01102
O-H2 0.00000 0.09160 0.07600 0.00760