The structure described by Cr4(PO4)3 crystallizes in the triclinic P-1 space group. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(4), one O(6), one O(7), and two equivalent O(5) atoms to form distorted CrO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra,  an edgeedge with one Cr(1)O5 trigonal bipyramid, and  an edgeedge with one Cr(4)O5 trigonal bipyramid. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), one O(3), and two equivalent O(9) atoms to form distorted CrO5 square pyramids that share  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and  an edgeedge with one Cr(2)O5 square pyramid. In the third Cr site, Cr(3) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(3), one O(6), and two equivalent O(8) atoms. In the fourth Cr site, Cr(4) is bonded to one O(10), one O(11), one O(12), one O(6), and one O(7) atom to form CrO5 trigonal bipyramids that share  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one Cr(1)O5 trigonal bipyramid. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(10), one O(2), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Cr(2)O5 square pyramids,  a cornercorner with one Cr(1)O5 trigonal bipyramid, and corners with two equivalent Cr(4)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(11), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(2)O5 square pyramid, corners with two equivalent Cr(1)O5 trigonal bipyramids, and corners with two equivalent Cr(4)O5 trigonal bipyramids. In the third P site, P(3) is bonded to one O(12), one O(5), one O(8), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Cr(2)O5 square pyramids,  a cornercorner with one Cr(4)O5 trigonal bipyramid, and corners with two equivalent Cr(1)O5 trigonal bipyramids. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Cr(2), one Cr(3), and one P(1) atom. In the second O site, O(2) is bonded in a linear geometry to one Cr(2) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Cr(2), one Cr(3), and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Cr(1) and one P(3) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Cr(1), one Cr(3), one Cr(4), and one P(1) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Cr(1), one Cr(4), and one P(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to two equivalent Cr(3) and one P(3) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to two equivalent Cr(2) and one P(3) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Cr(3), one Cr(4), and one P(1) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Cr(4) and one P(2) atom. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one Cr(4) and one P(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr4(PO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.615
_cell_length_b   8.207
_cell_length_c   9.679
_cell_angle_alpha   108.638
_cell_angle_beta   112.729
_cell_angle_gamma   94.211
_symmetry_Int_Tables_number   1
_cell_volume   515.078
_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
  Cr  Cr0  1  0.027  0.804  0.475  1.0
  Cr  Cr1  1  0.973  0.196  0.525  1.0
  Cr  Cr2  1  0.261  0.909  0.906  1.0
  Cr  Cr3  1  0.739  0.091  0.094  1.0
  Cr  Cr4  1  0.266  0.539  0.919  1.0
  Cr  Cr5  1  0.734  0.461  0.081  1.0
  Cr  Cr6  1  0.295  0.610  0.295  1.0
  Cr  Cr7  1  0.705  0.390  0.705  1.0
  P  P8  1  0.030  0.260  0.951  1.0
  P  P9  1  0.970  0.740  0.049  1.0
  P  P10  1  0.313  0.559  0.616  1.0
  P  P11  1  0.687  0.441  0.384  1.0
  P  P12  1  0.397  0.157  0.748  1.0
  P  P13  1  0.603  0.843  0.252  1.0
  O  O14  1  0.118  0.739  0.974  1.0
  O  O15  1  0.882  0.261  0.026  1.0
  O  O16  1  0.113  0.098  0.939  1.0
  O  O17  1  0.887  0.902  0.061  1.0
  O  O18  1  0.300  0.667  0.777  1.0
  O  O19  1  0.700  0.333  0.223  1.0
  O  O20  1  0.160  0.385  0.529  1.0
  O  O21  1  0.840  0.615  0.471  1.0
  O  O22  1  0.189  0.066  0.603  1.0
  O  O23  1  0.811  0.934  0.397  1.0
  O  O24  1  0.061  0.720  0.218  1.0
  O  O25  1  0.939  0.280  0.782  1.0
  O  O26  1  0.261  0.673  0.506  1.0
  O  O27  1  0.739  0.327  0.494  1.0
  O  O28  1  0.401  0.342  0.858  1.0
  O  O29  1  0.599  0.658  0.142  1.0
  O  O30  1  0.448  0.037  0.847  1.0
  O  O31  1  0.552  0.963  0.153  1.0
  O  O32  1  0.194  0.437  0.063  1.0
  O  O33  1  0.806  0.563  0.937  1.0
  O  O34  1  0.521  0.537  0.652  1.0
  O  O35  1  0.479  0.463  0.348  1.0
  O  O36  1  0.547  0.178  0.680  1.0
  O  O37  1  0.453  0.822  0.320  1.0
[/CIF]
.
The structure described by Cr4(PO4)3 crystallizes in the triclinic P-1 space group. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(4), one O(6), one O(7), and two equivalent O(5) atoms to form distorted CrO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra,  an edgeedge with one Cr(1)O5 trigonal bipyramid, and  an edgeedge with one Cr(4)O5 trigonal bipyramid. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), one O(3), and two equivalent O(9) atoms to form distorted CrO5 square pyramids that share  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and  an edgeedge with one Cr(2)O5 square pyramid. In the third Cr site, Cr(3) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(3), one O(6), and two equivalent O(8) atoms. In the fourth Cr site, Cr(4) is bonded to one O(10), one O(11), one O(12), one O(6), and one O(7) atom to form CrO5 trigonal bipyramids that share  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one Cr(1)O5 trigonal bipyramid. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(10), one O(2), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Cr(2)O5 square pyramids,  a cornercorner with one Cr(1)O5 trigonal bipyramid, and corners with two equivalent Cr(4)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(11), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(2)O5 square pyramid, corners with two equivalent Cr(1)O5 trigonal bipyramids, and corners with two equivalent Cr(4)O5 trigonal bipyramids. In the third P site, P(3) is bonded to one O(12), one O(5), one O(8), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Cr(2)O5 square pyramids,  a cornercorner with one Cr(4)O5 trigonal bipyramid, and corners with two equivalent Cr(1)O5 trigonal bipyramids. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Cr(2), one Cr(3), and one P(1) atom. In the second O site, O(2) is bonded in a linear geometry to one Cr(2) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Cr(2), one Cr(3), and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Cr(1) and one P(3) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Cr(1), one Cr(3), one Cr(4), and one P(1) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Cr(1), one Cr(4), and one P(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to two equivalent Cr(3) and one P(3) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to two equivalent Cr(2) and one P(3) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Cr(3), one Cr(4), and one P(1) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Cr(4) and one P(2) atom. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one Cr(4) and one P(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr4(PO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.615
_cell_length_b   8.207
_cell_length_c   9.679
_cell_angle_alpha   108.638
_cell_angle_beta   112.729
_cell_angle_gamma   94.211
_symmetry_Int_Tables_number   1
_cell_volume   515.078
_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
  Cr  Cr0  1  0.027  0.804  0.475  1.0
  Cr  Cr1  1  0.973  0.196  0.525  1.0
  Cr  Cr2  1  0.261  0.909  0.906  1.0
  Cr  Cr3  1  0.739  0.091  0.094  1.0
  Cr  Cr4  1  0.266  0.539  0.919  1.0
  Cr  Cr5  1  0.734  0.461  0.081  1.0
  Cr  Cr6  1  0.295  0.610  0.295  1.0
  Cr  Cr7  1  0.705  0.390  0.705  1.0
  P  P8  1  0.030  0.260  0.951  1.0
  P  P9  1  0.970  0.740  0.049  1.0
  P  P10  1  0.313  0.559  0.616  1.0
  P  P11  1  0.687  0.441  0.384  1.0
  P  P12  1  0.397  0.157  0.748  1.0
  P  P13  1  0.603  0.843  0.252  1.0
  O  O14  1  0.118  0.739  0.974  1.0
  O  O15  1  0.882  0.261  0.026  1.0
  O  O16  1  0.113  0.098  0.939  1.0
  O  O17  1  0.887  0.902  0.061  1.0
  O  O18  1  0.300  0.667  0.777  1.0
  O  O19  1  0.700  0.333  0.223  1.0
  O  O20  1  0.160  0.385  0.529  1.0
  O  O21  1  0.840  0.615  0.471  1.0
  O  O22  1  0.189  0.066  0.603  1.0
  O  O23  1  0.811  0.934  0.397  1.0
  O  O24  1  0.061  0.720  0.218  1.0
  O  O25  1  0.939  0.280  0.782  1.0
  O  O26  1  0.261  0.673  0.506  1.0
  O  O27  1  0.739  0.327  0.494  1.0
  O  O28  1  0.401  0.342  0.858  1.0
  O  O29  1  0.599  0.658  0.142  1.0
  O  O30  1  0.448  0.037  0.847  1.0
  O  O31  1  0.552  0.963  0.153  1.0
  O  O32  1  0.194  0.437  0.063  1.0
  O  O33  1  0.806  0.563  0.937  1.0
  O  O34  1  0.521  0.537  0.652  1.0
  O  O35  1  0.479  0.463  0.348  1.0
  O  O36  1  0.547  0.178  0.680  1.0
  O  O37  1  0.453  0.822  0.320  1.0
[/CIF]
.