The compound described by NaCaSiO4 crystallizes in the monoclinic P2_1/m space group. Na(1) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. Ca(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CaO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra and edges with two equivalent Ca(1)O6 octahedra. Si(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with six equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-57°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), two equivalent Ca(1), and one Si(1) atom to form distorted corner-sharing ONaCa2Si tetrahedra. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Ca(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Ca(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaCaSiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.158
_cell_length_b   5.408
_cell_length_c   5.449
_cell_angle_alpha   63.280
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   188.440
_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
  Na  Na0  1  0.750  0.719  0.659  1.0
  Na  Na1  1  0.250  0.281  0.341  1.0
  Ca  Ca2  1  0.500  0.000  0.000  1.0
  Ca  Ca3  1  0.000  0.000  0.000  1.0
  Si  Si4  1  0.250  0.623  0.668  1.0
  Si  Si5  1  0.750  0.377  0.332  1.0
  O  O6  1  0.250  0.289  0.767  1.0
  O  O7  1  0.750  0.711  0.233  1.0
  O  O8  1  0.750  0.196  0.667  1.0
  O  O9  1  0.250  0.804  0.333  1.0
  O  O10  1  0.440  0.712  0.784  1.0
  O  O11  1  0.940  0.288  0.216  1.0
  O  O12  1  0.560  0.288  0.216  1.0
  O  O13  1  0.060  0.712  0.784  1.0
[/CIF]
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The compound described by NaCaSiO4 crystallizes in the monoclinic P2_1/m space group. Na(1) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. Ca(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CaO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra and edges with two equivalent Ca(1)O6 octahedra. Si(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with six equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-57°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), two equivalent Ca(1), and one Si(1) atom to form distorted corner-sharing ONaCa2Si tetrahedra. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Ca(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Ca(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaCaSiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.158
_cell_length_b   5.408
_cell_length_c   5.449
_cell_angle_alpha   63.280
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   188.440
_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
  Na  Na0  1  0.750  0.719  0.659  1.0
  Na  Na1  1  0.250  0.281  0.341  1.0
  Ca  Ca2  1  0.500  0.000  0.000  1.0
  Ca  Ca3  1  0.000  0.000  0.000  1.0
  Si  Si4  1  0.250  0.623  0.668  1.0
  Si  Si5  1  0.750  0.377  0.332  1.0
  O  O6  1  0.250  0.289  0.767  1.0
  O  O7  1  0.750  0.711  0.233  1.0
  O  O8  1  0.750  0.196  0.667  1.0
  O  O9  1  0.250  0.804  0.333  1.0
  O  O10  1  0.440  0.712  0.784  1.0
  O  O11  1  0.940  0.288  0.216  1.0
  O  O12  1  0.560  0.288  0.216  1.0
  O  O13  1  0.060  0.712  0.784  1.0
[/CIF]
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