The material described by Na2FeAl(SiO3)4 is Esseneite-derived structured and crystallizes in the monoclinic C2 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. In the second Na site, Na(2) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with four equivalent Si(2)O4 tetrahedra, and edges with two equivalent Al(1)O6 octahedra. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form AlO6 octahedra that share corners with two equivalent Si(2)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(5), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Al(1)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-62°. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-60°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Na(1), one Fe(1), one Al(1), and one Si(1) atom. In the second O site, O(2) is bonded to one Na(2), one Fe(1), one Al(1), and one Si(2) atom to form a mixture of distorted corner and edge-sharing ONaAlFeSi tetrahedra. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Na(2), one Al(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Na(1), one Fe(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Na(1), one Na(2), one Si(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Na(1), one Na(2), one Si(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_Na2AlFe(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.532
_cell_length_b   6.532
_cell_length_c   5.335
_cell_angle_alpha   76.911
_cell_angle_beta   76.911
_cell_angle_gamma   84.512
_symmetry_Int_Tables_number   1
_cell_volume   215.716
_cell_formula_units_Z   1
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
  Na  Na0  1  0.299  0.701  0.500  1.0
  Na  Na1  1  0.701  0.299  0.000  1.0
  Al  Al2  1  0.901  0.099  0.500  1.0
  Fe  Fe3  1  0.098  0.902  0.000  1.0
  Si  Si4  1  0.801  0.615  0.484  1.0
  Si  Si5  1  0.385  0.199  0.516  1.0
  Si  Si6  1  0.199  0.378  0.021  1.0
  Si  Si7  1  0.622  0.801  0.979  1.0
  O  O8  1  0.961  0.813  0.395  1.0
  O  O9  1  0.187  0.039  0.605  1.0
  O  O10  1  0.029  0.190  0.131  1.0
  O  O11  1  0.810  0.971  0.869  1.0
  O  O12  1  0.895  0.377  0.548  1.0
  O  O13  1  0.623  0.105  0.452  1.0
  O  O14  1  0.100  0.615  0.951  1.0
  O  O15  1  0.385  0.900  0.049  1.0
  O  O16  1  0.658  0.643  0.258  1.0
  O  O17  1  0.357  0.342  0.742  1.0
  O  O18  1  0.348  0.361  0.238  1.0
  O  O19  1  0.639  0.652  0.762  1.0
[/CIF]
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The material described by Na2FeAl(SiO3)4 is Esseneite-derived structured and crystallizes in the monoclinic C2 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. In the second Na site, Na(2) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with four equivalent Si(2)O4 tetrahedra, and edges with two equivalent Al(1)O6 octahedra. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form AlO6 octahedra that share corners with two equivalent Si(2)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(5), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Al(1)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-62°. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-60°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Na(1), one Fe(1), one Al(1), and one Si(1) atom. In the second O site, O(2) is bonded to one Na(2), one Fe(1), one Al(1), and one Si(2) atom to form a mixture of distorted corner and edge-sharing ONaAlFeSi tetrahedra. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Na(2), one Al(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Na(1), one Fe(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Na(1), one Na(2), one Si(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Na(1), one Na(2), one Si(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_Na2AlFe(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.532
_cell_length_b   6.532
_cell_length_c   5.335
_cell_angle_alpha   76.911
_cell_angle_beta   76.911
_cell_angle_gamma   84.512
_symmetry_Int_Tables_number   1
_cell_volume   215.716
_cell_formula_units_Z   1
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
  Na  Na0  1  0.299  0.701  0.500  1.0
  Na  Na1  1  0.701  0.299  0.000  1.0
  Al  Al2  1  0.901  0.099  0.500  1.0
  Fe  Fe3  1  0.098  0.902  0.000  1.0
  Si  Si4  1  0.801  0.615  0.484  1.0
  Si  Si5  1  0.385  0.199  0.516  1.0
  Si  Si6  1  0.199  0.378  0.021  1.0
  Si  Si7  1  0.622  0.801  0.979  1.0
  O  O8  1  0.961  0.813  0.395  1.0
  O  O9  1  0.187  0.039  0.605  1.0
  O  O10  1  0.029  0.190  0.131  1.0
  O  O11  1  0.810  0.971  0.869  1.0
  O  O12  1  0.895  0.377  0.548  1.0
  O  O13  1  0.623  0.105  0.452  1.0
  O  O14  1  0.100  0.615  0.951  1.0
  O  O15  1  0.385  0.900  0.049  1.0
  O  O16  1  0.658  0.643  0.258  1.0
  O  O17  1  0.357  0.342  0.742  1.0
  O  O18  1  0.348  0.361  0.238  1.0
  O  O19  1  0.639  0.652  0.762  1.0
[/CIF]
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