The material structure described by MgCr2(PO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(10), one O(3), one O(4), one O(7), and one O(8) atom to form distorted MgO6 pentagonal pyramids that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 61°. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form CrO6 octahedra that share corners with two equivalent Cr(2)O6 octahedra,  a cornercorner with one Mg(1)O6 pentagonal pyramid, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one Mg(1)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 28-43°. In the second Cr site, Cr(2) is bonded to one O(1), one O(10), one O(3), one O(6), one O(8), and one O(9) atom to form CrO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and edges with two equivalent Mg(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 28-43°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra,  a cornercorner with one Mg(1)O6 pentagonal pyramid, and  an edgeedge with one Mg(1)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 36-55°. In the second P site, P(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and corners with two equivalent Mg(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 28-51°. 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 Cr(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(2), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Mg(1), one Cr(2), and one P(1) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Mg(1), one Cr(1), and one Cr(2) atom. is represented by the CIF file [CIF]
data_MgCr2(PO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.256
_cell_length_b   6.947
_cell_length_c   8.111
_cell_angle_alpha   90.669
_cell_angle_beta   40.580
_cell_angle_gamma   74.083
_symmetry_Int_Tables_number   1
_cell_volume   173.454
_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  0.585  0.241  0.629  1.0
  Cr  Cr1  1  0.491  0.498  0.006  1.0
  Cr  Cr2  1  0.511  0.992  0.987  1.0
  P  P3  1  0.483  0.245  0.338  1.0
  P  P4  1  0.518  0.745  0.644  1.0
  O  O5  1  0.271  0.134  0.330  1.0
  O  O6  1  0.646  0.377  0.149  1.0
  O  O7  1  0.666  0.891  0.678  1.0
  O  O8  1  0.437  0.576  0.788  1.0
  O  O9  1  0.872  0.615  0.343  1.0
  O  O10  1  0.110  0.897  0.755  1.0
  O  O11  1  0.157  0.374  0.639  1.0
  O  O12  1  0.865  0.093  0.259  1.0
  O  O13  1  0.508  0.738  0.046  1.0
  O  O14  1  0.494  0.253  0.917  1.0
[/CIF]
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The material structure described by MgCr2(PO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(10), one O(3), one O(4), one O(7), and one O(8) atom to form distorted MgO6 pentagonal pyramids that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 61°. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form CrO6 octahedra that share corners with two equivalent Cr(2)O6 octahedra,  a cornercorner with one Mg(1)O6 pentagonal pyramid, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one Mg(1)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 28-43°. In the second Cr site, Cr(2) is bonded to one O(1), one O(10), one O(3), one O(6), one O(8), and one O(9) atom to form CrO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and edges with two equivalent Mg(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 28-43°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra,  a cornercorner with one Mg(1)O6 pentagonal pyramid, and  an edgeedge with one Mg(1)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 36-55°. In the second P site, P(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and corners with two equivalent Mg(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 28-51°. 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 Cr(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(2), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Mg(1), one Cr(2), and one P(1) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Mg(1), one Cr(1), and one Cr(2) atom. is represented by the CIF file [CIF]
data_MgCr2(PO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.256
_cell_length_b   6.947
_cell_length_c   8.111
_cell_angle_alpha   90.669
_cell_angle_beta   40.580
_cell_angle_gamma   74.083
_symmetry_Int_Tables_number   1
_cell_volume   173.454
_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  0.585  0.241  0.629  1.0
  Cr  Cr1  1  0.491  0.498  0.006  1.0
  Cr  Cr2  1  0.511  0.992  0.987  1.0
  P  P3  1  0.483  0.245  0.338  1.0
  P  P4  1  0.518  0.745  0.644  1.0
  O  O5  1  0.271  0.134  0.330  1.0
  O  O6  1  0.646  0.377  0.149  1.0
  O  O7  1  0.666  0.891  0.678  1.0
  O  O8  1  0.437  0.576  0.788  1.0
  O  O9  1  0.872  0.615  0.343  1.0
  O  O10  1  0.110  0.897  0.755  1.0
  O  O11  1  0.157  0.374  0.639  1.0
  O  O12  1  0.865  0.093  0.259  1.0
  O  O13  1  0.508  0.738  0.046  1.0
  O  O14  1  0.494  0.253  0.917  1.0
[/CIF]
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