data_global
_chemical_name_mineral 'Scottyite'
loop_
_publ_author_name
'Yamada T'
'Hiroi Z'
'Takano M'
_journal_name_full 'Journal of Solid State Chemistry'
_journal_volume 156 
_journal_year 2001
_journal_page_first 101
_journal_page_last 109
_publ_section_title
;
 Spin-1/2 quantum antiferromagnetic chains with tunable superexchange
 interactions found in BaCu2(Si1-xGex)2O7
;
_database_code_amcsd 0018761
_chemical_compound_source 'Synthetic'
_chemical_formula_sum 'Ba Cu2 Si2 O7'
_cell_length_a 6.86058
_cell_length_b 13.17507
_cell_length_c 6.89589
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 623.310
_exptl_crystal_density_diffrn      4.610
_symmetry_space_group_name_H-M 'P n m a'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,1/2-y,z'
  '-x,1/2+y,-z'
  '1/2-x,1/2+y,1/2+z'
  '1/2+x,1/2-y,1/2-z'
  '1/2+x,y,1/2-z'
  '1/2-x,-y,1/2+z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Ba  -0.01150   0.25000   0.95580   0.02242
Cu   0.22140   0.00520   0.79270   0.02280
Si   0.00450   0.13370   0.47320   0.00836
O1   0.07750   0.25000   0.47810  -0.00013
O2  -0.16170   0.13110   0.62380   0.02495
O3  -0.06980   0.11550   0.26190   0.02951
O4   0.18090   0.06490   0.52990   0.00735