#------------------------------------------------------------------------------
#$Date: 2008-03-10 10:25:41 +0200 (Mon, 10 Mar 2008) $
#$Revision: 255 $
#$URL: file:///home/coder/svn-repositories/cod/cif/9/9001104.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/
#
# All data on this site have been placed in the public domain by the
# contributors.
#
data_9001104
loop_
_publ_author_name
'Downs J W'
'Ross F K'
_publ_section_title
;
 Neutron-diffraction study of bertrandite
 Note: O2y has been corrected
;
_journal_name_full               'American Mineralogist'
_journal_page_first              979
_journal_page_last               983
_journal_volume                  72
_journal_year                    1987
_chemical_formula_sum            'Si2 Be4 H2 O9'
_chemical_name_mineral           Bertrandite
_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                   8.7135
_cell_length_b                   15.268
_cell_length_c                   4.5683
_cell_volume                     607.756
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
Si 0.32510 0.11410 0.65400
Be1 0.17260 0.05249 0.15620
Be2 0.32640 0.22023 0.15090
H1 0.00000 0.20060 0.42030
H2 0.50000 0.36750 0.45300
O1 0.28990 0.12430 0.00000
O2 0.20950 0.04300 0.50650
O3 0.29380 0.20910 0.50120
O4 0.50000 0.08470 0.59160
O5 0.50000 0.25530 0.08770
O6 0.00000 0.08760 0.09780
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
Si 0.01030 0.00300 0.00900 -0.00080 -0.00040 0.00000
Be1 0.01040 0.00540 0.01070 0.00080 -0.00070 -0.00060
Be2 0.01260 0.00590 0.01110 0.00030 -0.00050 0.00130
H1 0.02100 0.02890 0.03510 0.00000 0.00000 -0.01760
H2 0.02950 0.02500 0.04070 0.00000 0.00000 -0.01530
O1 0.01360 0.00420 0.00960 -0.00150 0.00180 -0.00050
O2 0.01260 0.00530 0.01010 -0.00200 -0.00120 0.00030
O3 0.01530 0.00470 0.00990 0.00150 -0.00600 0.00050
O4 0.00770 0.00920 0.01720 0.00000 0.00000 -0.00270
O5 0.01050 0.01010 0.01580 0.00000 0.00000 0.00280
O6 0.01220 0.01040 0.01370 0.00000 0.00000 0.00110