The compound described by BaY2(Si2O7)F2 crystallizes in the triclinic P-1 space group. Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(5), one O(6), two equivalent O(4), one F(1), and one F(2) atom. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(7), and two equivalent O(2) atoms. In the second Y site, Y(2) is bonded in a 8-coordinate geometry to one O(5), one O(7), two equivalent O(6), two equivalent F(1), and two equivalent F(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Y(1), one Si(1), and one Si(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), two equivalent Y(1), and one Si(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(1), one Y(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Y(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted tetrahedral geometry to one Ba(1), one Y(1), one Y(2), and one Si(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Y(2), and one Si(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Y(1), one Y(2), and one Si(1) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1) and two equivalent Y(2) atoms. In the second F site, F(2) is bonded in a trigonal planar geometry to one Ba(1) and two equivalent Y(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaY2Si2O7F2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.227
_cell_length_b   6.917
_cell_length_c   11.877
_cell_angle_alpha   92.995
_cell_angle_beta   102.107
_cell_angle_gamma   111.348
_symmetry_Int_Tables_number   1
_cell_volume   387.120
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ba  Ba0  1  0.596  0.382  0.750  1.0
  Ba  Ba1  1  0.404  0.618  0.250  1.0
  Y  Y2  1  0.325  0.798  0.877  1.0
  Y  Y3  1  0.675  0.202  0.123  1.0
  Y  Y4  1  0.182  0.805  0.544  1.0
  Y  Y5  1  0.818  0.195  0.456  1.0
  Si  Si6  1  0.772  0.931  0.718  1.0
  Si  Si7  1  0.228  0.069  0.282  1.0
  Si  Si8  1  0.128  0.249  0.934  1.0
  Si  Si9  1  0.872  0.751  0.066  1.0
  O  O10  1  0.818  0.069  0.847  1.0
  O  O11  1  0.182  0.931  0.153  1.0
  O  O12  1  0.374  0.148  0.944  1.0
  O  O13  1  0.626  0.852  0.056  1.0
  O  O14  1  0.074  0.298  0.060  1.0
  O  O15  1  0.926  0.702  0.940  1.0
  O  O16  1  0.205  0.446  0.860  1.0
  O  O17  1  0.795  0.554  0.140  1.0
  O  O18  1  0.477  0.728  0.710  1.0
  O  O19  1  0.523  0.272  0.290  1.0
  O  O20  1  0.673  0.058  0.617  1.0
  O  O21  1  0.327  0.942  0.383  1.0
  O  O22  1  0.049  0.878  0.716  1.0
  O  O23  1  0.951  0.122  0.284  1.0
  F  F24  1  0.788  0.828  0.443  1.0
  F  F25  1  0.212  0.172  0.557  1.0
  F  F26  1  0.168  0.519  0.435  1.0
  F  F27  1  0.832  0.481  0.565  1.0
[/CIF]
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The compound described by BaY2(Si2O7)F2 crystallizes in the triclinic P-1 space group. Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(5), one O(6), two equivalent O(4), one F(1), and one F(2) atom. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(7), and two equivalent O(2) atoms. In the second Y site, Y(2) is bonded in a 8-coordinate geometry to one O(5), one O(7), two equivalent O(6), two equivalent F(1), and two equivalent F(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Y(1), one Si(1), and one Si(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), two equivalent Y(1), and one Si(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(1), one Y(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Y(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted tetrahedral geometry to one Ba(1), one Y(1), one Y(2), and one Si(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Y(2), and one Si(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Y(1), one Y(2), and one Si(1) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1) and two equivalent Y(2) atoms. In the second F site, F(2) is bonded in a trigonal planar geometry to one Ba(1) and two equivalent Y(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaY2Si2O7F2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.227
_cell_length_b   6.917
_cell_length_c   11.877
_cell_angle_alpha   92.995
_cell_angle_beta   102.107
_cell_angle_gamma   111.348
_symmetry_Int_Tables_number   1
_cell_volume   387.120
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ba  Ba0  1  0.596  0.382  0.750  1.0
  Ba  Ba1  1  0.404  0.618  0.250  1.0
  Y  Y2  1  0.325  0.798  0.877  1.0
  Y  Y3  1  0.675  0.202  0.123  1.0
  Y  Y4  1  0.182  0.805  0.544  1.0
  Y  Y5  1  0.818  0.195  0.456  1.0
  Si  Si6  1  0.772  0.931  0.718  1.0
  Si  Si7  1  0.228  0.069  0.282  1.0
  Si  Si8  1  0.128  0.249  0.934  1.0
  Si  Si9  1  0.872  0.751  0.066  1.0
  O  O10  1  0.818  0.069  0.847  1.0
  O  O11  1  0.182  0.931  0.153  1.0
  O  O12  1  0.374  0.148  0.944  1.0
  O  O13  1  0.626  0.852  0.056  1.0
  O  O14  1  0.074  0.298  0.060  1.0
  O  O15  1  0.926  0.702  0.940  1.0
  O  O16  1  0.205  0.446  0.860  1.0
  O  O17  1  0.795  0.554  0.140  1.0
  O  O18  1  0.477  0.728  0.710  1.0
  O  O19  1  0.523  0.272  0.290  1.0
  O  O20  1  0.673  0.058  0.617  1.0
  O  O21  1  0.327  0.942  0.383  1.0
  O  O22  1  0.049  0.878  0.716  1.0
  O  O23  1  0.951  0.122  0.284  1.0
  F  F24  1  0.788  0.828  0.443  1.0
  F  F25  1  0.212  0.172  0.557  1.0
  F  F26  1  0.168  0.519  0.435  1.0
  F  F27  1  0.832  0.481  0.565  1.0
[/CIF]
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