The crystal structure described by Mg3Co3(AsO4)4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(3), one O(4), one O(5), and one O(7) atom to form distorted MgO5 square pyramids that share corners with two equivalent As(1)O4 tetrahedra, corners with three equivalent As(2)O4 tetrahedra,  a cornercorner with one Co(1)O5 trigonal bipyramid, and  an edgeedge with one Co(1)O5 trigonal bipyramid. In the second Mg site, Mg(2) is bonded to two equivalent O(2), two equivalent O(6), and two equivalent O(8) atoms to form MgO6 octahedra that share corners with two equivalent As(2)O4 tetrahedra, corners with four equivalent As(1)O4 tetrahedra, and edges with two equivalent Co(1)O5 trigonal bipyramids. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(2), one O(4), one O(7), and one O(8) atom to form CoO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O5 square pyramid, corners with two equivalent As(2)O4 tetrahedra, corners with three equivalent As(1)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra, and  an edgeedge with one Mg(1)O5 square pyramid. In the second Co site, Co(2) is bonded in a square co-planar geometry to two equivalent O(5) and two equivalent O(7) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(1), one O(4), one O(6), and one O(8) atom to form AsO4 tetrahedra that share corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, and corners with three equivalent Co(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 46-59°. In the second As site, As(2) is bonded to one O(2), one O(3), one O(5), and one O(7) atom to form AsO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra, corners with three equivalent Mg(1)O5 square pyramids, and corners with two equivalent Co(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 56°. There are eight inequivalent O sites. In the first O site, O(7) is bonded to one Mg(1), one Co(1), one Co(2), and one As(2) atom to form corner-sharing OMgCo2As tetrahedra. In the second O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Mg(2), one Co(1), and one As(1) atom. In the third O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Co(1), and one As(1) atom. In the fourth O site, O(2) is bonded in a distorted trigonal planar geometry to one Mg(2), one Co(1), and one As(2) atom. In the fifth O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one As(2) atom. In the sixth O site, O(4) is bonded in a trigonal planar geometry to one Mg(1), one Co(1), and one As(1) atom. In the seventh O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Co(2), and one As(2) atom. In the eighth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Mg(2) and one As(1) atom. is represented by the CIF file [CIF]
data_Mg3Co3(AsO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.160
_cell_length_b   8.676
_cell_length_c   16.050
_cell_angle_alpha   67.716
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   664.893
_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  0.546  0.312  0.212  1.0
  Mg  Mg1  1  0.046  0.688  0.288  1.0
  Mg  Mg2  1  0.454  0.688  0.788  1.0
  Mg  Mg3  1  0.954  0.312  0.712  1.0
  Mg  Mg4  1  0.500  0.000  0.500  1.0
  Mg  Mg5  1  0.000  0.000  0.000  1.0
  Co  Co6  1  0.490  0.203  0.625  1.0
  Co  Co7  1  0.510  0.797  0.375  1.0
  Co  Co8  1  0.990  0.797  0.875  1.0
  Co  Co9  1  0.010  0.203  0.125  1.0
  Co  Co10  1  0.000  0.500  0.500  1.0
  Co  Co11  1  0.500  0.500  0.000  1.0
  As  As12  1  0.992  0.037  0.352  1.0
  As  As13  1  0.497  0.417  0.397  1.0
  As  As14  1  0.997  0.583  0.103  1.0
  As  As15  1  0.003  0.417  0.897  1.0
  As  As16  1  0.008  0.963  0.648  1.0
  As  As17  1  0.503  0.583  0.603  1.0
  As  As18  1  0.508  0.037  0.852  1.0
  As  As19  1  0.492  0.963  0.148  1.0
  O  O20  1  0.404  0.810  0.253  1.0
  O  O21  1  0.944  0.756  0.008  1.0
  O  O22  1  0.409  0.400  0.300  1.0
  O  O23  1  0.394  0.154  0.152  1.0
  O  O24  1  0.591  0.600  0.700  1.0
  O  O25  1  0.096  0.810  0.753  1.0
  O  O26  1  0.909  0.600  0.200  1.0
  O  O27  1  0.704  0.511  0.893  1.0
  O  O28  1  0.676  0.088  0.927  1.0
  O  O29  1  0.596  0.190  0.747  1.0
  O  O30  1  0.106  0.154  0.652  1.0
  O  O31  1  0.296  0.489  0.107  1.0
  O  O32  1  0.286  0.571  0.408  1.0
  O  O33  1  0.324  0.912  0.073  1.0
  O  O34  1  0.676  0.978  0.632  1.0
  O  O35  1  0.176  0.022  0.868  1.0
  O  O36  1  0.786  0.429  0.092  1.0
  O  O37  1  0.091  0.400  0.800  1.0
  O  O38  1  0.176  0.912  0.573  1.0
  O  O39  1  0.204  0.489  0.607  1.0
  O  O40  1  0.824  0.978  0.132  1.0
  O  O41  1  0.324  0.022  0.368  1.0
  O  O42  1  0.056  0.244  0.992  1.0
  O  O43  1  0.444  0.244  0.492  1.0
  O  O44  1  0.714  0.429  0.592  1.0
  O  O45  1  0.904  0.190  0.247  1.0
  O  O46  1  0.606  0.846  0.848  1.0
  O  O47  1  0.824  0.088  0.427  1.0
  O  O48  1  0.556  0.756  0.508  1.0
  O  O49  1  0.796  0.511  0.393  1.0
  O  O50  1  0.214  0.571  0.908  1.0
  O  O51  1  0.894  0.846  0.348  1.0
[/CIF]
.
The crystal structure described by Mg3Co3(AsO4)4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(3), one O(4), one O(5), and one O(7) atom to form distorted MgO5 square pyramids that share corners with two equivalent As(1)O4 tetrahedra, corners with three equivalent As(2)O4 tetrahedra,  a cornercorner with one Co(1)O5 trigonal bipyramid, and  an edgeedge with one Co(1)O5 trigonal bipyramid. In the second Mg site, Mg(2) is bonded to two equivalent O(2), two equivalent O(6), and two equivalent O(8) atoms to form MgO6 octahedra that share corners with two equivalent As(2)O4 tetrahedra, corners with four equivalent As(1)O4 tetrahedra, and edges with two equivalent Co(1)O5 trigonal bipyramids. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(2), one O(4), one O(7), and one O(8) atom to form CoO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O5 square pyramid, corners with two equivalent As(2)O4 tetrahedra, corners with three equivalent As(1)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra, and  an edgeedge with one Mg(1)O5 square pyramid. In the second Co site, Co(2) is bonded in a square co-planar geometry to two equivalent O(5) and two equivalent O(7) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(1), one O(4), one O(6), and one O(8) atom to form AsO4 tetrahedra that share corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, and corners with three equivalent Co(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 46-59°. In the second As site, As(2) is bonded to one O(2), one O(3), one O(5), and one O(7) atom to form AsO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra, corners with three equivalent Mg(1)O5 square pyramids, and corners with two equivalent Co(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 56°. There are eight inequivalent O sites. In the first O site, O(7) is bonded to one Mg(1), one Co(1), one Co(2), and one As(2) atom to form corner-sharing OMgCo2As tetrahedra. In the second O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Mg(2), one Co(1), and one As(1) atom. In the third O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Co(1), and one As(1) atom. In the fourth O site, O(2) is bonded in a distorted trigonal planar geometry to one Mg(2), one Co(1), and one As(2) atom. In the fifth O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one As(2) atom. In the sixth O site, O(4) is bonded in a trigonal planar geometry to one Mg(1), one Co(1), and one As(1) atom. In the seventh O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Co(2), and one As(2) atom. In the eighth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Mg(2) and one As(1) atom. is represented by the CIF file [CIF]
data_Mg3Co3(AsO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.160
_cell_length_b   8.676
_cell_length_c   16.050
_cell_angle_alpha   67.716
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   664.893
_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  0.546  0.312  0.212  1.0
  Mg  Mg1  1  0.046  0.688  0.288  1.0
  Mg  Mg2  1  0.454  0.688  0.788  1.0
  Mg  Mg3  1  0.954  0.312  0.712  1.0
  Mg  Mg4  1  0.500  0.000  0.500  1.0
  Mg  Mg5  1  0.000  0.000  0.000  1.0
  Co  Co6  1  0.490  0.203  0.625  1.0
  Co  Co7  1  0.510  0.797  0.375  1.0
  Co  Co8  1  0.990  0.797  0.875  1.0
  Co  Co9  1  0.010  0.203  0.125  1.0
  Co  Co10  1  0.000  0.500  0.500  1.0
  Co  Co11  1  0.500  0.500  0.000  1.0
  As  As12  1  0.992  0.037  0.352  1.0
  As  As13  1  0.497  0.417  0.397  1.0
  As  As14  1  0.997  0.583  0.103  1.0
  As  As15  1  0.003  0.417  0.897  1.0
  As  As16  1  0.008  0.963  0.648  1.0
  As  As17  1  0.503  0.583  0.603  1.0
  As  As18  1  0.508  0.037  0.852  1.0
  As  As19  1  0.492  0.963  0.148  1.0
  O  O20  1  0.404  0.810  0.253  1.0
  O  O21  1  0.944  0.756  0.008  1.0
  O  O22  1  0.409  0.400  0.300  1.0
  O  O23  1  0.394  0.154  0.152  1.0
  O  O24  1  0.591  0.600  0.700  1.0
  O  O25  1  0.096  0.810  0.753  1.0
  O  O26  1  0.909  0.600  0.200  1.0
  O  O27  1  0.704  0.511  0.893  1.0
  O  O28  1  0.676  0.088  0.927  1.0
  O  O29  1  0.596  0.190  0.747  1.0
  O  O30  1  0.106  0.154  0.652  1.0
  O  O31  1  0.296  0.489  0.107  1.0
  O  O32  1  0.286  0.571  0.408  1.0
  O  O33  1  0.324  0.912  0.073  1.0
  O  O34  1  0.676  0.978  0.632  1.0
  O  O35  1  0.176  0.022  0.868  1.0
  O  O36  1  0.786  0.429  0.092  1.0
  O  O37  1  0.091  0.400  0.800  1.0
  O  O38  1  0.176  0.912  0.573  1.0
  O  O39  1  0.204  0.489  0.607  1.0
  O  O40  1  0.824  0.978  0.132  1.0
  O  O41  1  0.324  0.022  0.368  1.0
  O  O42  1  0.056  0.244  0.992  1.0
  O  O43  1  0.444  0.244  0.492  1.0
  O  O44  1  0.714  0.429  0.592  1.0
  O  O45  1  0.904  0.190  0.247  1.0
  O  O46  1  0.606  0.846  0.848  1.0
  O  O47  1  0.824  0.088  0.427  1.0
  O  O48  1  0.556  0.756  0.508  1.0
  O  O49  1  0.796  0.511  0.393  1.0
  O  O50  1  0.214  0.571  0.908  1.0
  O  O51  1  0.894  0.846  0.348  1.0
[/CIF]
.