The compound described by NaCaMgAl(SiO3)4 is Esseneite-derived structured and crystallizes in the monoclinic C2 space group. Na(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. Ca(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. Mg(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with two equivalent Si(2)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Al(1)O6 octahedra. Al(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form AlO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with four equivalent Si(2)O4 tetrahedra, and edges with two equivalent Mg(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 Al(1)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-61°. 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 Mg(1)O6 octahedra, corners with two equivalent Al(1)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-63°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Ca(1), one Mg(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Na(1), one Al(1), and one Si(2) atom. In the third O site, O(3) is bonded to one Na(1), one Mg(1), one Al(1), and one Si(1) atom to form distorted ONaMgAlSi tetrahedra that share  a cornercorner with one O(3)NaMgAlSi tetrahedra, corners with two equivalent O(4)CaMgAlSi tetrahedra,  an edgeedge with one O(4)CaMgAlSi tetrahedra, and  an edgeedge with one O(3)NaMgAlSi tetrahedra. In the fourth O site, O(4) is bonded to one Ca(1), one Mg(1), one Al(1), and one Si(2) atom to form distorted OCaMgAlSi tetrahedra that share  a cornercorner with one O(4)CaMgAlSi tetrahedra, corners with two equivalent O(3)NaMgAlSi tetrahedra,  an edgeedge with one O(4)CaMgAlSi tetrahedra, and  an edgeedge with one O(3)NaMgAlSi tetrahedra. In the fifth O site, O(5) is bonded in a 4-coordinate 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 file [CIF]
data_NaCaMgAl(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.565
_cell_length_b   6.565
_cell_length_c   5.319
_cell_angle_alpha   77.241
_cell_angle_beta   77.241
_cell_angle_gamma   84.763
_symmetry_Int_Tables_number   1
_cell_volume   217.855
_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  0.300  0.700  0.500  1.0
  Ca  Ca1  1  0.699  0.301  0.000  1.0
  Mg  Mg2  1  0.910  0.090  0.500  1.0
  Al  Al3  1  0.099  0.901  0.000  1.0
  Si  Si4  1  0.806  0.623  0.471  1.0
  Si  Si5  1  0.377  0.194  0.529  1.0
  Si  Si6  1  0.196  0.384  0.018  1.0
  Si  Si7  1  0.616  0.804  0.982  1.0
  O  O8  1  0.894  0.388  0.561  1.0
  O  O9  1  0.612  0.106  0.439  1.0
  O  O10  1  0.105  0.622  0.948  1.0
  O  O11  1  0.378  0.895  0.052  1.0
  O  O12  1  0.973  0.808  0.361  1.0
  O  O13  1  0.192  0.027  0.639  1.0
  O  O14  1  0.034  0.194  0.097  1.0
  O  O15  1  0.806  0.966  0.903  1.0
  O  O16  1  0.657  0.630  0.251  1.0
  O  O17  1  0.370  0.343  0.749  1.0
  O  O18  1  0.334  0.357  0.250  1.0
  O  O19  1  0.643  0.666  0.750  1.0
[/CIF]
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The compound described by NaCaMgAl(SiO3)4 is Esseneite-derived structured and crystallizes in the monoclinic C2 space group. Na(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. Ca(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. Mg(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with two equivalent Si(2)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Al(1)O6 octahedra. Al(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form AlO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with four equivalent Si(2)O4 tetrahedra, and edges with two equivalent Mg(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 Al(1)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-61°. 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 Mg(1)O6 octahedra, corners with two equivalent Al(1)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-63°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Ca(1), one Mg(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Na(1), one Al(1), and one Si(2) atom. In the third O site, O(3) is bonded to one Na(1), one Mg(1), one Al(1), and one Si(1) atom to form distorted ONaMgAlSi tetrahedra that share  a cornercorner with one O(3)NaMgAlSi tetrahedra, corners with two equivalent O(4)CaMgAlSi tetrahedra,  an edgeedge with one O(4)CaMgAlSi tetrahedra, and  an edgeedge with one O(3)NaMgAlSi tetrahedra. In the fourth O site, O(4) is bonded to one Ca(1), one Mg(1), one Al(1), and one Si(2) atom to form distorted OCaMgAlSi tetrahedra that share  a cornercorner with one O(4)CaMgAlSi tetrahedra, corners with two equivalent O(3)NaMgAlSi tetrahedra,  an edgeedge with one O(4)CaMgAlSi tetrahedra, and  an edgeedge with one O(3)NaMgAlSi tetrahedra. In the fifth O site, O(5) is bonded in a 4-coordinate 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 file [CIF]
data_NaCaMgAl(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.565
_cell_length_b   6.565
_cell_length_c   5.319
_cell_angle_alpha   77.241
_cell_angle_beta   77.241
_cell_angle_gamma   84.763
_symmetry_Int_Tables_number   1
_cell_volume   217.855
_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  0.300  0.700  0.500  1.0
  Ca  Ca1  1  0.699  0.301  0.000  1.0
  Mg  Mg2  1  0.910  0.090  0.500  1.0
  Al  Al3  1  0.099  0.901  0.000  1.0
  Si  Si4  1  0.806  0.623  0.471  1.0
  Si  Si5  1  0.377  0.194  0.529  1.0
  Si  Si6  1  0.196  0.384  0.018  1.0
  Si  Si7  1  0.616  0.804  0.982  1.0
  O  O8  1  0.894  0.388  0.561  1.0
  O  O9  1  0.612  0.106  0.439  1.0
  O  O10  1  0.105  0.622  0.948  1.0
  O  O11  1  0.378  0.895  0.052  1.0
  O  O12  1  0.973  0.808  0.361  1.0
  O  O13  1  0.192  0.027  0.639  1.0
  O  O14  1  0.034  0.194  0.097  1.0
  O  O15  1  0.806  0.966  0.903  1.0
  O  O16  1  0.657  0.630  0.251  1.0
  O  O17  1  0.370  0.343  0.749  1.0
  O  O18  1  0.334  0.357  0.250  1.0
  O  O19  1  0.643  0.666  0.750  1.0
[/CIF]
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