The material described by FePb2As2O9 crystallizes in the monoclinic P2_1/m space group. Fe(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms to form FeO6 octahedra that share corners with two equivalent As(1)O4 tetrahedra, corners with two equivalent As(2)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), and two equivalent O(6) atoms. In the second Pb site, Pb(2) is bonded in a 6-coordinate geometry to one O(4), one O(5), two equivalent O(6), and two equivalent O(7) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(1), one O(5), and two equivalent O(7) atoms to form AsO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. In the second As site, As(2) is bonded to one O(2), one O(3), and two equivalent O(6) atoms to form AsO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Pb(1) and one As(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Pb(1) and one As(2) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to two equivalent Fe(1) and one As(2) atom. In the fourth O site, O(4) is bonded in a distorted water-like geometry to two equivalent Fe(1) and one Pb(2) atom. In the fifth O site, O(5) is bonded in a distorted linear geometry to one Pb(2) and one As(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Pb(1), one Pb(2), and one As(2) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Fe(1), one Pb(2), and one As(1) atom. is represented by the CIF card [CIF]
data_FeAs2Pb2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.014
_cell_length_b   8.105
_cell_length_c   9.034
_cell_angle_alpha   66.676
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   404.389
_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
  Fe  Fe0  1  0.500  0.000  0.000  1.0
  Fe  Fe1  1  0.000  0.000  0.000  1.0
  As  As2  1  0.250  0.973  0.337  1.0
  As  As3  1  0.750  0.027  0.663  1.0
  As  As4  1  0.250  0.568  0.172  1.0
  As  As5  1  0.750  0.432  0.828  1.0
  Pb  Pb6  1  0.250  0.695  0.754  1.0
  Pb  Pb7  1  0.750  0.305  0.246  1.0
  Pb  Pb8  1  0.250  0.295  0.614  1.0
  Pb  Pb9  1  0.750  0.705  0.386  1.0
  O  O10  1  0.250  0.749  0.460  1.0
  O  O11  1  0.750  0.251  0.540  1.0
  O  O12  1  0.250  0.473  0.035  1.0
  O  O13  1  0.750  0.527  0.965  1.0
  O  O14  1  0.250  0.804  0.069  1.0
  O  O15  1  0.750  0.196  0.931  1.0
  O  O16  1  0.250  0.151  0.926  1.0
  O  O17  1  0.750  0.849  0.074  1.0
  O  O18  1  0.250  0.112  0.435  1.0
  O  O19  1  0.750  0.888  0.565  1.0
  O  O20  1  0.483  0.507  0.294  1.0
  O  O21  1  0.517  0.493  0.706  1.0
  O  O22  1  0.983  0.493  0.706  1.0
  O  O23  1  0.017  0.507  0.294  1.0
  O  O24  1  0.990  0.990  0.782  1.0
  O  O25  1  0.010  0.010  0.218  1.0
  O  O26  1  0.490  0.010  0.218  1.0
  O  O27  1  0.510  0.990  0.782  1.0
[/CIF]
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The material described by FePb2As2O9 crystallizes in the monoclinic P2_1/m space group. Fe(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms to form FeO6 octahedra that share corners with two equivalent As(1)O4 tetrahedra, corners with two equivalent As(2)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), and two equivalent O(6) atoms. In the second Pb site, Pb(2) is bonded in a 6-coordinate geometry to one O(4), one O(5), two equivalent O(6), and two equivalent O(7) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(1), one O(5), and two equivalent O(7) atoms to form AsO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. In the second As site, As(2) is bonded to one O(2), one O(3), and two equivalent O(6) atoms to form AsO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Pb(1) and one As(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Pb(1) and one As(2) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to two equivalent Fe(1) and one As(2) atom. In the fourth O site, O(4) is bonded in a distorted water-like geometry to two equivalent Fe(1) and one Pb(2) atom. In the fifth O site, O(5) is bonded in a distorted linear geometry to one Pb(2) and one As(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Pb(1), one Pb(2), and one As(2) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Fe(1), one Pb(2), and one As(1) atom. is represented by the CIF card [CIF]
data_FeAs2Pb2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.014
_cell_length_b   8.105
_cell_length_c   9.034
_cell_angle_alpha   66.676
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   404.389
_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
  Fe  Fe0  1  0.500  0.000  0.000  1.0
  Fe  Fe1  1  0.000  0.000  0.000  1.0
  As  As2  1  0.250  0.973  0.337  1.0
  As  As3  1  0.750  0.027  0.663  1.0
  As  As4  1  0.250  0.568  0.172  1.0
  As  As5  1  0.750  0.432  0.828  1.0
  Pb  Pb6  1  0.250  0.695  0.754  1.0
  Pb  Pb7  1  0.750  0.305  0.246  1.0
  Pb  Pb8  1  0.250  0.295  0.614  1.0
  Pb  Pb9  1  0.750  0.705  0.386  1.0
  O  O10  1  0.250  0.749  0.460  1.0
  O  O11  1  0.750  0.251  0.540  1.0
  O  O12  1  0.250  0.473  0.035  1.0
  O  O13  1  0.750  0.527  0.965  1.0
  O  O14  1  0.250  0.804  0.069  1.0
  O  O15  1  0.750  0.196  0.931  1.0
  O  O16  1  0.250  0.151  0.926  1.0
  O  O17  1  0.750  0.849  0.074  1.0
  O  O18  1  0.250  0.112  0.435  1.0
  O  O19  1  0.750  0.888  0.565  1.0
  O  O20  1  0.483  0.507  0.294  1.0
  O  O21  1  0.517  0.493  0.706  1.0
  O  O22  1  0.983  0.493  0.706  1.0
  O  O23  1  0.017  0.507  0.294  1.0
  O  O24  1  0.990  0.990  0.782  1.0
  O  O25  1  0.010  0.010  0.218  1.0
  O  O26  1  0.490  0.010  0.218  1.0
  O  O27  1  0.510  0.990  0.782  1.0
[/CIF]
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