The compound described by MgCo2(SiO3)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(12), one O(2), one O(7), and one O(8) atom. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(10), one O(11), one O(12), one O(5), one O(6), and one O(9) atom to form distorted CoO6 octahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and edges with two equivalent Co(2)O6 octahedra. In the second Co site, Co(2) is bonded to one O(10), one O(11), one O(12), one O(7), one O(8), and one O(9) atom to form CoO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, corners with two equivalent Si(4)O4 tetrahedra, and edges with two equivalent Co(1)O6 octahedra. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(11), one O(4), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, and corners with two equivalent Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-61°. In the second Si site, Si(2) is bonded to one O(12), one O(2), one O(3), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, and corners with two equivalent Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-63°. In the third Si site, Si(3) is bonded to one O(1), one O(4), one O(8), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-62°. In the fourth Si site, Si(4) is bonded to one O(10), one O(2), one O(3), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-57°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Si(1), and one Si(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Mg(1), one Si(2), and one Si(4) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(4) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Co(1) and one Si(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Co(1) and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(2), and one Si(4) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(2), and one Si(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one Si(3) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one Si(4) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Mg(1), one Co(1), one Co(2), and one Si(1) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Mg(1), one Co(1), one Co(2), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCo2(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.346
_cell_length_b   6.476
_cell_length_c   6.610
_cell_angle_alpha   83.087
_cell_angle_beta   74.510
_cell_angle_gamma   75.378
_symmetry_Int_Tables_number   1
_cell_volume   213.080
_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
  Mg  Mg0  1  0.250  0.726  0.271  1.0
  Co  Co1  1  0.262  0.107  0.892  1.0
  Co  Co2  1  0.752  0.915  0.089  1.0
  Si  Si3  1  0.231  0.203  0.390  1.0
  Si  Si4  1  0.264  0.616  0.794  1.0
  Si  Si5  1  0.739  0.383  0.207  1.0
  Si  Si6  1  0.761  0.795  0.616  1.0
  O  O7  1  0.427  0.377  0.339  1.0
  O  O8  1  0.064  0.658  0.635  1.0
  O  O9  1  0.554  0.638  0.645  1.0
  O  O10  1  0.945  0.351  0.358  1.0
  O  O11  1  0.210  0.090  0.621  1.0
  O  O12  1  0.278  0.381  0.911  1.0
  O  O13  1  0.846  0.875  0.370  1.0
  O  O14  1  0.671  0.633  0.120  1.0
  O  O15  1  0.844  0.192  0.041  1.0
  O  O16  1  0.642  0.961  0.806  1.0
  O  O17  1  0.351  0.023  0.209  1.0
  O  O18  1  0.158  0.793  0.977  1.0
[/CIF]
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The compound described by MgCo2(SiO3)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(12), one O(2), one O(7), and one O(8) atom. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(10), one O(11), one O(12), one O(5), one O(6), and one O(9) atom to form distorted CoO6 octahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and edges with two equivalent Co(2)O6 octahedra. In the second Co site, Co(2) is bonded to one O(10), one O(11), one O(12), one O(7), one O(8), and one O(9) atom to form CoO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, corners with two equivalent Si(4)O4 tetrahedra, and edges with two equivalent Co(1)O6 octahedra. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(11), one O(4), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, and corners with two equivalent Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-61°. In the second Si site, Si(2) is bonded to one O(12), one O(2), one O(3), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, and corners with two equivalent Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-63°. In the third Si site, Si(3) is bonded to one O(1), one O(4), one O(8), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-62°. In the fourth Si site, Si(4) is bonded to one O(10), one O(2), one O(3), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-57°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Si(1), and one Si(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Mg(1), one Si(2), and one Si(4) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(4) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Co(1) and one Si(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Co(1) and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(2), and one Si(4) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(2), and one Si(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one Si(3) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one Si(4) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Mg(1), one Co(1), one Co(2), and one Si(1) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Mg(1), one Co(1), one Co(2), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCo2(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.346
_cell_length_b   6.476
_cell_length_c   6.610
_cell_angle_alpha   83.087
_cell_angle_beta   74.510
_cell_angle_gamma   75.378
_symmetry_Int_Tables_number   1
_cell_volume   213.080
_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
  Mg  Mg0  1  0.250  0.726  0.271  1.0
  Co  Co1  1  0.262  0.107  0.892  1.0
  Co  Co2  1  0.752  0.915  0.089  1.0
  Si  Si3  1  0.231  0.203  0.390  1.0
  Si  Si4  1  0.264  0.616  0.794  1.0
  Si  Si5  1  0.739  0.383  0.207  1.0
  Si  Si6  1  0.761  0.795  0.616  1.0
  O  O7  1  0.427  0.377  0.339  1.0
  O  O8  1  0.064  0.658  0.635  1.0
  O  O9  1  0.554  0.638  0.645  1.0
  O  O10  1  0.945  0.351  0.358  1.0
  O  O11  1  0.210  0.090  0.621  1.0
  O  O12  1  0.278  0.381  0.911  1.0
  O  O13  1  0.846  0.875  0.370  1.0
  O  O14  1  0.671  0.633  0.120  1.0
  O  O15  1  0.844  0.192  0.041  1.0
  O  O16  1  0.642  0.961  0.806  1.0
  O  O17  1  0.351  0.023  0.209  1.0
  O  O18  1  0.158  0.793  0.977  1.0
[/CIF]
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