The structure described by MgCr2(GeO3)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(6), one O(8), and one O(9) atom. There are two inequivalent Cr sites. In the first Cr site, Cr(1) 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 CrO6 octahedra that share  a cornercorner with one Ge(3)O4 tetrahedra,  a cornercorner with one Ge(4)O4 tetrahedra, corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O5 trigonal bipyramids, and edges with two equivalent Cr(2)O6 octahedra. In the second Cr site, Cr(2) 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 CrO6 octahedra that share  a cornercorner with one Ge(1)O4 tetrahedra, corners with two equivalent Ge(3)O4 tetrahedra, corners with two equivalent Ge(4)O4 tetrahedra, edges with two equivalent Cr(1)O6 octahedra, and  an edgeedge with one Ge(2)O5 trigonal bipyramid. There are four inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(4), one O(8), and one O(9) atom to form GeO4 tetrahedra that share  a cornercorner with one Cr(2)O6 octahedra, corners with two equivalent Cr(1)O6 octahedra, and corners with two equivalent Ge(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-62°. In the second Ge site, Ge(2) is bonded to one O(10), one O(2), one O(3), one O(5), and one O(7) atom to form distorted GeO5 trigonal bipyramids that share corners with two equivalent Cr(1)O6 octahedra,  a cornercorner with one Ge(4)O4 tetrahedra, corners with two equivalent Ge(3)O4 tetrahedra, and  an edgeedge with one Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-49°. In the third Ge site, Ge(3) is bonded to one O(11), one O(2), one O(3), and one O(6) atom to form GeO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and corners with two equivalent Ge(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 9-63°. In the fourth Ge site, Ge(4) is bonded to one O(1), one O(12), one O(4), and one O(5) atom to form GeO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, corners with two equivalent Ge(1)O4 tetrahedra, and  a cornercorner with one Ge(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 44-64°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Ge(1) and one Ge(4) atom. In the second O site, O(2) is bonded in a T-shaped geometry to one Mg(1), one Ge(2), and one Ge(3) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Mg(1), one Ge(2), and one Ge(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ge(1) and one Ge(4) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Cr(2), one Ge(2), and one Ge(4) atom. In the sixth O site, O(6) is bonded in a T-shaped geometry to one Mg(1), one Cr(2), and one Ge(3) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Cr(1) and one Ge(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one Ge(1) atom. In the ninth O site, O(9) is bonded in a distorted see-saw-like geometry to one Mg(1), one Cr(1), one Cr(2), and one Ge(1) atom. In the tenth O site, O(10) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(2), and one Ge(2) atom. In the eleventh O site, O(11) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(2), and one Ge(3) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cr(2), and one Ge(4) atom. is represented by the CIF card [CIF]
data_MgCr2(GeO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.588
_cell_length_b   6.700
_cell_length_c   6.825
_cell_angle_alpha   82.998
_cell_angle_beta   76.745
_cell_angle_gamma   74.507
_symmetry_Int_Tables_number   1
_cell_volume   239.191
_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  0.850  0.455  0.807  1.0
  Cr  Cr1  1  0.758  0.924  0.086  1.0
  Cr  Cr2  1  0.260  0.096  0.917  1.0
  Ge  Ge3  1  0.758  0.391  0.238  1.0
  Ge  Ge4  1  0.699  0.865  0.604  1.0
  Ge  Ge5  1  0.239  0.652  0.783  1.0
  Ge  Ge6  1  0.283  0.198  0.392  1.0
  O  O7  1  0.445  0.397  0.368  1.0
  O  O8  1  0.007  0.686  0.634  1.0
  O  O9  1  0.565  0.635  0.671  1.0
  O  O10  1  0.955  0.338  0.420  1.0
  O  O11  1  0.295  0.042  0.620  1.0
  O  O12  1  0.227  0.395  0.864  1.0
  O  O13  1  0.773  0.964  0.361  1.0
  O  O14  1  0.744  0.623  0.081  1.0
  O  O15  1  0.859  0.213  0.031  1.0
  O  O16  1  0.637  0.003  0.824  1.0
  O  O17  1  0.141  0.830  0.974  1.0
  O  O18  1  0.375  0.052  0.177  1.0
[/CIF]
.
The structure described by MgCr2(GeO3)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(6), one O(8), and one O(9) atom. There are two inequivalent Cr sites. In the first Cr site, Cr(1) 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 CrO6 octahedra that share  a cornercorner with one Ge(3)O4 tetrahedra,  a cornercorner with one Ge(4)O4 tetrahedra, corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O5 trigonal bipyramids, and edges with two equivalent Cr(2)O6 octahedra. In the second Cr site, Cr(2) 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 CrO6 octahedra that share  a cornercorner with one Ge(1)O4 tetrahedra, corners with two equivalent Ge(3)O4 tetrahedra, corners with two equivalent Ge(4)O4 tetrahedra, edges with two equivalent Cr(1)O6 octahedra, and  an edgeedge with one Ge(2)O5 trigonal bipyramid. There are four inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(4), one O(8), and one O(9) atom to form GeO4 tetrahedra that share  a cornercorner with one Cr(2)O6 octahedra, corners with two equivalent Cr(1)O6 octahedra, and corners with two equivalent Ge(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-62°. In the second Ge site, Ge(2) is bonded to one O(10), one O(2), one O(3), one O(5), and one O(7) atom to form distorted GeO5 trigonal bipyramids that share corners with two equivalent Cr(1)O6 octahedra,  a cornercorner with one Ge(4)O4 tetrahedra, corners with two equivalent Ge(3)O4 tetrahedra, and  an edgeedge with one Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-49°. In the third Ge site, Ge(3) is bonded to one O(11), one O(2), one O(3), and one O(6) atom to form GeO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and corners with two equivalent Ge(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 9-63°. In the fourth Ge site, Ge(4) is bonded to one O(1), one O(12), one O(4), and one O(5) atom to form GeO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, corners with two equivalent Ge(1)O4 tetrahedra, and  a cornercorner with one Ge(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 44-64°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Ge(1) and one Ge(4) atom. In the second O site, O(2) is bonded in a T-shaped geometry to one Mg(1), one Ge(2), and one Ge(3) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Mg(1), one Ge(2), and one Ge(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ge(1) and one Ge(4) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Cr(2), one Ge(2), and one Ge(4) atom. In the sixth O site, O(6) is bonded in a T-shaped geometry to one Mg(1), one Cr(2), and one Ge(3) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Cr(1) and one Ge(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one Ge(1) atom. In the ninth O site, O(9) is bonded in a distorted see-saw-like geometry to one Mg(1), one Cr(1), one Cr(2), and one Ge(1) atom. In the tenth O site, O(10) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(2), and one Ge(2) atom. In the eleventh O site, O(11) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(2), and one Ge(3) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cr(2), and one Ge(4) atom. is represented by the CIF card [CIF]
data_MgCr2(GeO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.588
_cell_length_b   6.700
_cell_length_c   6.825
_cell_angle_alpha   82.998
_cell_angle_beta   76.745
_cell_angle_gamma   74.507
_symmetry_Int_Tables_number   1
_cell_volume   239.191
_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  0.850  0.455  0.807  1.0
  Cr  Cr1  1  0.758  0.924  0.086  1.0
  Cr  Cr2  1  0.260  0.096  0.917  1.0
  Ge  Ge3  1  0.758  0.391  0.238  1.0
  Ge  Ge4  1  0.699  0.865  0.604  1.0
  Ge  Ge5  1  0.239  0.652  0.783  1.0
  Ge  Ge6  1  0.283  0.198  0.392  1.0
  O  O7  1  0.445  0.397  0.368  1.0
  O  O8  1  0.007  0.686  0.634  1.0
  O  O9  1  0.565  0.635  0.671  1.0
  O  O10  1  0.955  0.338  0.420  1.0
  O  O11  1  0.295  0.042  0.620  1.0
  O  O12  1  0.227  0.395  0.864  1.0
  O  O13  1  0.773  0.964  0.361  1.0
  O  O14  1  0.744  0.623  0.081  1.0
  O  O15  1  0.859  0.213  0.031  1.0
  O  O16  1  0.637  0.003  0.824  1.0
  O  O17  1  0.141  0.830  0.974  1.0
  O  O18  1  0.375  0.052  0.177  1.0
[/CIF]
.