data_global
_chemical_name_mineral 'Feldspar'
loop_
_publ_author_name
'Benna P'
'Bruno E'
_journal_name_full 'American Mineralogist'
_journal_volume 88 
_journal_year 2003
_journal_page_first 1532
_journal_page_last 1541
_publ_section_title
;
 Single-crystal in situ high-temperature structural investigation of the I-1 - I2/c phase
 transition in Ca0.2Sr0.8Al2Si2O8 feldspar
 T = 620 C
;
_database_code_amcsd 0003181
_chemical_formula_sum '(Ca.2 Sr.8) Si2 Al2 O8'
_cell_length_a 8.386
_cell_length_b 12.970
_cell_length_c 14.283
_cell_angle_alpha 90
_cell_angle_beta 115.46
_cell_angle_gamma 90
_cell_volume 1402.642
_exptl_crystal_density_diffrn      2.995
_symmetry_space_group_name_H-M 'I 1 2/c 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,1/2+z'
  'x,-y,1/2+z'
  '1/2+x,1/2-y,+z'
  '-x,y,1/2-z'
  '1/2-x,1/2+y,-z'
  '-x,-y,-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_occupancy
_atom_site_U_iso_or_equiv
Ca   0.27230  -0.00190   0.06610   0.20000   0.04100
Sr   0.27230  -0.00190   0.06610   0.80000   0.04100
SiT1(0)   0.00700   0.17520   0.10820   1.00000   0.02000
AlT1(z)   0.00300   0.17810   0.61650   1.00000   0.02000
AlT2(0)   0.69550   0.12090   0.17080   1.00000   0.02000
SiT2(z)   0.68630   0.11330   0.67220   1.00000   0.01900
OA(1)   0.00530   0.13030   0.00050   1.00000   0.03000
OA(2)   0.59300   0.00020   0.14260   1.00000   0.03000
OB(0)   0.82900   0.12730   0.10620   1.00000   0.03800
OB(z)   0.80980   0.12760   0.61250   1.00000   0.04000
OC(0)   0.01370   0.29850   0.11800   1.00000   0.03700
OC(z)   0.01980   0.31000   0.63110   1.00000   0.03500
OD(0)   0.18650   0.12520   0.19570   1.00000   0.04200
OD(z)   0.19790   0.11900   0.70380   1.00000   0.03900
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
Ca 0.02200 0.05500 0.04300 0.00000 0.00900 -0.00400
Sr 0.02200 0.05500 0.04300 0.00000 0.00900 -0.00400
SiT1(0) 0.02100 0.02500 0.01700 -0.00400 0.01000 -0.00100
AlT1(z) 0.02200 0.02300 0.01800 -0.00400 0.01000 -0.00100
AlT2(0) 0.01900 0.02000 0.02100 -0.00100 0.00800 0.00000
SiT2(z) 0.01800 0.01800 0.02200 -0.00200 0.00800 -0.00100
OA(1) 0.03900 0.03600 0.01800 -0.00100 0.01600 -0.00200
OA(2) 0.02300 0.01900 0.04400 0.00100 0.01000 0.00100
OB(0) 0.03200 0.04500 0.04500 -0.01200 0.02500 -0.00500
OB(z) 0.03000 0.05000 0.05100 -0.00700 0.02700 0.00500
OC(0) 0.03500 0.02800 0.04300 -0.01000 0.01300 -0.00700
OC(z) 0.03000 0.02600 0.04800 -0.01100 0.01600 -0.00600
OD(0) 0.03500 0.05500 0.02400 0.00500 0.00300 0.00500
OD(z) 0.03500 0.04300 0.02700 0.00300 0.00400 0.00200