The structure described by NaCaFe(SiO3)4 crystallizes in the monoclinic C2 space group. 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. Ca(1) 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(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with two equivalent Si(2)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. 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 corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-50°. 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 Fe(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Na(1), one Fe(1), and one Si(1) atom. In the second O site, O(2) is bonded in a water-like geometry to one Ca(1) and one Si(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Na(1), one Fe(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Na(1), one Ca(1), 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 Ca(1), one Si(1), and one Si(2) atom. is represented by the CIF card [CIF]
data_NaCaFe(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.272
_cell_length_b   6.721
_cell_length_c   6.721
_cell_angle_alpha   84.834
_cell_angle_beta   78.260
_cell_angle_gamma   78.260
_symmetry_Int_Tables_number   1
_cell_volume   228.017
_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  0.250  0.298  0.702  1.0
  Ca  Ca1  1  0.750  0.714  0.286  1.0
  Fe  Fe2  1  0.750  0.086  0.914  1.0
  Si  Si3  1  0.734  0.618  0.804  1.0
  Si  Si4  1  0.766  0.196  0.382  1.0
  Si  Si5  1  0.279  0.372  0.199  1.0
  Si  Si6  1  0.221  0.801  0.628  1.0
  O  O7  1  0.810  0.386  0.896  1.0
  O  O8  1  0.690  0.104  0.614  1.0
  O  O9  1  0.192  0.602  0.107  1.0
  O  O10  1  0.308  0.893  0.398  1.0
  O  O11  1  0.675  0.798  0.962  1.0
  O  O12  1  0.825  0.038  0.202  1.0
  O  O13  1  0.386  0.212  0.018  1.0
  O  O14  1  0.114  0.982  0.788  1.0
  O  O15  1  0.497  0.642  0.671  1.0
  O  O16  1  0.003  0.329  0.358  1.0
  O  O17  1  0.499  0.371  0.345  1.0
  O  O18  1  0.001  0.655  0.629  1.0
[/CIF]
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The structure described by NaCaFe(SiO3)4 crystallizes in the monoclinic C2 space group. 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. Ca(1) 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(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with two equivalent Si(2)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. 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 corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-50°. 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 Fe(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Na(1), one Fe(1), and one Si(1) atom. In the second O site, O(2) is bonded in a water-like geometry to one Ca(1) and one Si(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(1), one Fe(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Na(1), one Fe(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Na(1), one Ca(1), 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 Ca(1), one Si(1), and one Si(2) atom. is represented by the CIF card [CIF]
data_NaCaFe(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.272
_cell_length_b   6.721
_cell_length_c   6.721
_cell_angle_alpha   84.834
_cell_angle_beta   78.260
_cell_angle_gamma   78.260
_symmetry_Int_Tables_number   1
_cell_volume   228.017
_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  0.250  0.298  0.702  1.0
  Ca  Ca1  1  0.750  0.714  0.286  1.0
  Fe  Fe2  1  0.750  0.086  0.914  1.0
  Si  Si3  1  0.734  0.618  0.804  1.0
  Si  Si4  1  0.766  0.196  0.382  1.0
  Si  Si5  1  0.279  0.372  0.199  1.0
  Si  Si6  1  0.221  0.801  0.628  1.0
  O  O7  1  0.810  0.386  0.896  1.0
  O  O8  1  0.690  0.104  0.614  1.0
  O  O9  1  0.192  0.602  0.107  1.0
  O  O10  1  0.308  0.893  0.398  1.0
  O  O11  1  0.675  0.798  0.962  1.0
  O  O12  1  0.825  0.038  0.202  1.0
  O  O13  1  0.386  0.212  0.018  1.0
  O  O14  1  0.114  0.982  0.788  1.0
  O  O15  1  0.497  0.642  0.671  1.0
  O  O16  1  0.003  0.329  0.358  1.0
  O  O17  1  0.499  0.371  0.345  1.0
  O  O18  1  0.001  0.655  0.629  1.0
[/CIF]
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