#------------------------------------------------------------------------------
#$Date: 2009-11-16 03:43:51 +0200 (Mon, 16 Nov 2009) $
#$Revision: 853 $
#$URL: file:///home/coder/svn-repositories/cod/cif/1/1000052.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_1000052
_space_group_IT_number           155
_symmetry_space_group_name_Hall  'R 3 2"'
_symmetry_space_group_name_H-M   'R 3 2 :H'
_[local]_cod_cif_authors_sg_H-M  'R 3 2 H'
loop_
_publ_author_name
'Dollase, W A'
'Reeder, R J'
_publ_section_title
;
Crystal structure refinement of Huntite Ca Mg~3~ (C O~3~)~4~ with X-ray 
powder data
;
_journal_coden_ASTM              AMMIAY
_journal_name_full               'American Mineralogist'
_journal_page_first              163
_journal_page_last               166
_journal_volume                  71
_journal_year                    1986
_chemical_compound_source        'from Tea Tree Gully, Australia'
_chemical_formula_structural     'Ca Mg3 (C O3)4'
_chemical_formula_sum            'Ca Mg3 O12'
_chemical_name_mineral           Huntite
_chemical_name_systematic        'Calcium trimagnesium carbonate'
_symmetry_cell_setting           trigonal
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_formula_units_Z            3
_cell_length_a                   9.5027(6)
_cell_length_b                   9.5027(6)
_cell_length_c                   7.8212(6)
_cell_volume                     611.6
_refine_ls_R_factor_all          0.053
loop_
_symmetry_equiv_pos_as_xyz
x,y,z
-y,x-y,z
y-x,-x,z
y,x,-z
x-y,-y,-z
-x,y-x,-z
1/3+x,2/3+y,2/3+z
2/3+x,1/3+y,1/3+z
1/3-y,2/3+x-y,2/3+z
2/3-y,1/3+x-y,1/3+z
1/3-x+y,2/3-x,2/3+z
2/3-x+y,1/3-x,1/3+z
1/3+y,2/3+x,2/3-z
2/3+y,1/3+x,1/3-z
1/3+x-y,2/3-y,2/3-z
2/3+x-y,1/3-y,1/3-z
1/3-x,2/3-x+y,2/3-z
2/3-x,1/3-x+y,1/3-z
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_symmetry_multiplicity
_atom_site_Wyckoff_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_attached_hydrogens
_atom_site_calc_flag
Ca1 Ca2+ 3 a 0. 0. 0. 1. 0 d
Mg1 Mg2+ 9 d 0.5443(7) 0. 0. 1. 0 d
C1 C4+ 3 b 0. 0. 0.5 1. 0 d
C2 C4+ 9 e 0.4535(20) 0. 0.5 1. 0 d
O1 O2- 9 e 0.8663(15) 0. 0.5 1. 0 d
O2 O2- 9 e 0.5895(13) 0. 0.5 1. 0 d
O3 O2- 18 f 0.4569(11) 0.1355(12) 0.5161(11) 1. 0 d
loop_
_atom_type_symbol
_atom_type_oxidation_number
Ca2+ 2.000
Mg2+ 2.000
C4+ 4.000
O2- -2.000