The compound described by MgVSiO5 crystallizes in the triclinic P1 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(10), one O(3), one O(4), and one O(6) atom to form MgO5 square pyramids that share corners with two equivalent V(1)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with three equivalent Si(1)O4 tetrahedra, and edges with two equivalent V(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-60°. In the second Mg site, Mg(2) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(7), one O(8), and one O(9) atom. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(10), one O(2), one O(3), one O(5), one O(8), and one O(9) atom to form VO6 octahedra that share corners with two equivalent V(2)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 43-47°. In the second V site, V(2) is bonded to one O(1), one O(10), one O(4), one O(6), one O(7), and one O(9) atom to form VO6 octahedra that share corners with two equivalent V(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and edges with two equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 43-47°. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(6), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent V(1)O6 octahedra, corners with two equivalent V(2)O6 octahedra, and corners with three equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 45-67°. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(5), and one O(7) atom to form SiO4 tetrahedra that share corners with two equivalent V(1)O6 octahedra, corners with two equivalent V(2)O6 octahedra, and  a cornercorner with one Mg(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 43-63°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(2), and one Si(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Mg(2), one V(1), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(2), one V(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted tetrahedral geometry to one Mg(1), one Mg(2), one V(2), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(2), one V(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(2), and one Si(1) atom. In the seventh O site, O(7) is bonded in a trigonal non-coplanar geometry to one Mg(2), one V(2), and one Si(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Mg(2), one V(1), and one Si(1) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Mg(2), one V(1), and one V(2) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(1), and one V(2) atom. is represented by the CIF file [CIF]
data_MgVSiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.145
_cell_length_b   5.407
_cell_length_c   6.981
_cell_angle_alpha   104.764
_cell_angle_beta   101.156
_cell_angle_gamma   108.231
_symmetry_Int_Tables_number   1
_cell_volume   170.293
_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
  Mg  Mg0  1  0.351  0.221  0.804  1.0
  Mg  Mg1  1  0.639  0.814  0.297  1.0
  O  O2  1  0.686  0.614  0.881  1.0
  O  O3  1  0.028  0.143  0.346  1.0
  O  O4  1  0.983  0.864  0.662  1.0
  O  O5  1  0.305  0.366  0.107  1.0
  O  O6  1  0.600  0.269  0.448  1.0
  O  O7  1  0.695  0.120  0.881  1.0
  O  O8  1  0.298  0.869  0.119  1.0
  O  O9  1  0.424  0.709  0.531  1.0
  O  O10  1  0.898  0.573  0.254  1.0
  O  O11  1  0.102  0.441  0.753  1.0
  Si  Si12  1  0.695  0.823  0.743  1.0
  Si  Si13  1  0.307  0.171  0.258  1.0
  V  V14  1  0.011  0.494  0.512  1.0
  V  V15  1  0.987  0.505  0.015  1.0
[/CIF]
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The compound described by MgVSiO5 crystallizes in the triclinic P1 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(10), one O(3), one O(4), and one O(6) atom to form MgO5 square pyramids that share corners with two equivalent V(1)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with three equivalent Si(1)O4 tetrahedra, and edges with two equivalent V(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-60°. In the second Mg site, Mg(2) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(7), one O(8), and one O(9) atom. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(10), one O(2), one O(3), one O(5), one O(8), and one O(9) atom to form VO6 octahedra that share corners with two equivalent V(2)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 43-47°. In the second V site, V(2) is bonded to one O(1), one O(10), one O(4), one O(6), one O(7), and one O(9) atom to form VO6 octahedra that share corners with two equivalent V(1)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and edges with two equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 43-47°. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(6), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent V(1)O6 octahedra, corners with two equivalent V(2)O6 octahedra, and corners with three equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 45-67°. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(5), and one O(7) atom to form SiO4 tetrahedra that share corners with two equivalent V(1)O6 octahedra, corners with two equivalent V(2)O6 octahedra, and  a cornercorner with one Mg(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 43-63°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(2), and one Si(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Mg(2), one V(1), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(2), one V(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted tetrahedral geometry to one Mg(1), one Mg(2), one V(2), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(2), one V(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(2), and one Si(1) atom. In the seventh O site, O(7) is bonded in a trigonal non-coplanar geometry to one Mg(2), one V(2), and one Si(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Mg(2), one V(1), and one Si(1) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Mg(2), one V(1), and one V(2) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(1), and one V(2) atom. is represented by the CIF file [CIF]
data_MgVSiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.145
_cell_length_b   5.407
_cell_length_c   6.981
_cell_angle_alpha   104.764
_cell_angle_beta   101.156
_cell_angle_gamma   108.231
_symmetry_Int_Tables_number   1
_cell_volume   170.293
_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
  Mg  Mg0  1  0.351  0.221  0.804  1.0
  Mg  Mg1  1  0.639  0.814  0.297  1.0
  O  O2  1  0.686  0.614  0.881  1.0
  O  O3  1  0.028  0.143  0.346  1.0
  O  O4  1  0.983  0.864  0.662  1.0
  O  O5  1  0.305  0.366  0.107  1.0
  O  O6  1  0.600  0.269  0.448  1.0
  O  O7  1  0.695  0.120  0.881  1.0
  O  O8  1  0.298  0.869  0.119  1.0
  O  O9  1  0.424  0.709  0.531  1.0
  O  O10  1  0.898  0.573  0.254  1.0
  O  O11  1  0.102  0.441  0.753  1.0
  Si  Si12  1  0.695  0.823  0.743  1.0
  Si  Si13  1  0.307  0.171  0.258  1.0
  V  V14  1  0.011  0.494  0.512  1.0
  V  V15  1  0.987  0.505  0.015  1.0
[/CIF]
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