The structure described by MgTiAs2O7 crystallizes in the monoclinic P2_1/c space group. Mg(1) is bonded to one O(1), one O(5), one O(6), and two equivalent O(3) atoms to form MgO5 trigonal bipyramids that share corners with two equivalent Ti(1)O4 tetrahedra, corners with three equivalent As(1)O4 tetrahedra, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. Ti(1) is bonded to one O(1), one O(2), one O(5), and one O(7) atom to form TiO4 tetrahedra that share  a cornercorner with one As(1)O4 tetrahedra and corners with two equivalent Mg(1)O5 trigonal bipyramids. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form AsO4 tetrahedra that share  a cornercorner with one Ti(1)O4 tetrahedra and corners with three equivalent Mg(1)O5 trigonal bipyramids. In the second As site, As(2) is bonded in a 3-coordinate geometry to one O(4), one O(5), and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a trigonal planar geometry to one Mg(1), one Ti(1), and one As(2) atom. In the second O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Mg(1) and one As(1) atom. In the third O site, O(7) is bonded in a bent 120 degrees geometry to one Ti(1) and one As(2) atom. In the fourth O site, O(1) is bonded in a bent 120 degrees geometry to one Mg(1) and one Ti(1) atom. In the fifth O site, O(2) is bonded in a linear geometry to one Ti(1) and one As(1) atom. In the sixth O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one As(1) atom. In the seventh O site, O(4) is bonded in a bent 120 degrees geometry to one As(1) and one As(2) atom. is represented by the CIF card [CIF]
data_MgTiAs2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.566
_cell_length_b   8.361
_cell_length_c   10.894
_cell_angle_alpha   55.257
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   641.190
_cell_formula_units_Z   4
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  0.117  0.670  0.878  1.0
  Mg  Mg1  1  0.617  0.330  0.622  1.0
  Mg  Mg2  1  0.883  0.330  0.122  1.0
  Mg  Mg3  1  0.383  0.670  0.378  1.0
  Ti  Ti4  1  0.973  0.154  0.713  1.0
  Ti  Ti5  1  0.473  0.846  0.787  1.0
  Ti  Ti6  1  0.027  0.846  0.287  1.0
  Ti  Ti7  1  0.527  0.154  0.213  1.0
  As  As8  1  0.774  0.562  0.765  1.0
  As  As9  1  0.274  0.438  0.735  1.0
  As  As10  1  0.226  0.438  0.235  1.0
  As  As11  1  0.726  0.562  0.265  1.0
  As  As12  1  0.696  0.991  0.966  1.0
  As  As13  1  0.196  0.009  0.534  1.0
  As  As14  1  0.304  0.009  0.034  1.0
  As  As15  1  0.804  0.991  0.466  1.0
  O  O16  1  0.675  0.254  0.085  1.0
  O  O17  1  0.175  0.746  0.415  1.0
  O  O18  1  0.325  0.746  0.915  1.0
  O  O19  1  0.825  0.254  0.585  1.0
  O  O20  1  0.612  0.674  0.778  1.0
  O  O21  1  0.112  0.326  0.722  1.0
  O  O22  1  0.388  0.326  0.222  1.0
  O  O23  1  0.888  0.674  0.278  1.0
  O  O24  1  0.911  0.529  0.892  1.0
  O  O25  1  0.411  0.471  0.608  1.0
  O  O26  1  0.089  0.471  0.108  1.0
  O  O27  1  0.589  0.529  0.392  1.0
  O  O28  1  0.847  0.720  0.582  1.0
  O  O29  1  0.347  0.280  0.918  1.0
  O  O30  1  0.153  0.280  0.418  1.0
  O  O31  1  0.653  0.720  0.082  1.0
  O  O32  1  0.921  0.032  0.308  1.0
  O  O33  1  0.421  0.968  0.192  1.0
  O  O34  1  0.079  0.968  0.692  1.0
  O  O35  1  0.579  0.032  0.808  1.0
  O  O36  1  0.767  0.360  0.271  1.0
  O  O37  1  0.267  0.640  0.229  1.0
  O  O38  1  0.233  0.640  0.729  1.0
  O  O39  1  0.733  0.360  0.771  1.0
  O  O40  1  0.617  0.976  0.397  1.0
  O  O41  1  0.117  0.024  0.103  1.0
  O  O42  1  0.383  0.024  0.603  1.0
  O  O43  1  0.883  0.976  0.897  1.0
[/CIF]
.
The structure described by MgTiAs2O7 crystallizes in the monoclinic P2_1/c space group. Mg(1) is bonded to one O(1), one O(5), one O(6), and two equivalent O(3) atoms to form MgO5 trigonal bipyramids that share corners with two equivalent Ti(1)O4 tetrahedra, corners with three equivalent As(1)O4 tetrahedra, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. Ti(1) is bonded to one O(1), one O(2), one O(5), and one O(7) atom to form TiO4 tetrahedra that share  a cornercorner with one As(1)O4 tetrahedra and corners with two equivalent Mg(1)O5 trigonal bipyramids. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form AsO4 tetrahedra that share  a cornercorner with one Ti(1)O4 tetrahedra and corners with three equivalent Mg(1)O5 trigonal bipyramids. In the second As site, As(2) is bonded in a 3-coordinate geometry to one O(4), one O(5), and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a trigonal planar geometry to one Mg(1), one Ti(1), and one As(2) atom. In the second O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Mg(1) and one As(1) atom. In the third O site, O(7) is bonded in a bent 120 degrees geometry to one Ti(1) and one As(2) atom. In the fourth O site, O(1) is bonded in a bent 120 degrees geometry to one Mg(1) and one Ti(1) atom. In the fifth O site, O(2) is bonded in a linear geometry to one Ti(1) and one As(1) atom. In the sixth O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one As(1) atom. In the seventh O site, O(4) is bonded in a bent 120 degrees geometry to one As(1) and one As(2) atom. is represented by the CIF card [CIF]
data_MgTiAs2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.566
_cell_length_b   8.361
_cell_length_c   10.894
_cell_angle_alpha   55.257
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   641.190
_cell_formula_units_Z   4
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  0.117  0.670  0.878  1.0
  Mg  Mg1  1  0.617  0.330  0.622  1.0
  Mg  Mg2  1  0.883  0.330  0.122  1.0
  Mg  Mg3  1  0.383  0.670  0.378  1.0
  Ti  Ti4  1  0.973  0.154  0.713  1.0
  Ti  Ti5  1  0.473  0.846  0.787  1.0
  Ti  Ti6  1  0.027  0.846  0.287  1.0
  Ti  Ti7  1  0.527  0.154  0.213  1.0
  As  As8  1  0.774  0.562  0.765  1.0
  As  As9  1  0.274  0.438  0.735  1.0
  As  As10  1  0.226  0.438  0.235  1.0
  As  As11  1  0.726  0.562  0.265  1.0
  As  As12  1  0.696  0.991  0.966  1.0
  As  As13  1  0.196  0.009  0.534  1.0
  As  As14  1  0.304  0.009  0.034  1.0
  As  As15  1  0.804  0.991  0.466  1.0
  O  O16  1  0.675  0.254  0.085  1.0
  O  O17  1  0.175  0.746  0.415  1.0
  O  O18  1  0.325  0.746  0.915  1.0
  O  O19  1  0.825  0.254  0.585  1.0
  O  O20  1  0.612  0.674  0.778  1.0
  O  O21  1  0.112  0.326  0.722  1.0
  O  O22  1  0.388  0.326  0.222  1.0
  O  O23  1  0.888  0.674  0.278  1.0
  O  O24  1  0.911  0.529  0.892  1.0
  O  O25  1  0.411  0.471  0.608  1.0
  O  O26  1  0.089  0.471  0.108  1.0
  O  O27  1  0.589  0.529  0.392  1.0
  O  O28  1  0.847  0.720  0.582  1.0
  O  O29  1  0.347  0.280  0.918  1.0
  O  O30  1  0.153  0.280  0.418  1.0
  O  O31  1  0.653  0.720  0.082  1.0
  O  O32  1  0.921  0.032  0.308  1.0
  O  O33  1  0.421  0.968  0.192  1.0
  O  O34  1  0.079  0.968  0.692  1.0
  O  O35  1  0.579  0.032  0.808  1.0
  O  O36  1  0.767  0.360  0.271  1.0
  O  O37  1  0.267  0.640  0.229  1.0
  O  O38  1  0.233  0.640  0.729  1.0
  O  O39  1  0.733  0.360  0.771  1.0
  O  O40  1  0.617  0.976  0.397  1.0
  O  O41  1  0.117  0.024  0.103  1.0
  O  O42  1  0.383  0.024  0.603  1.0
  O  O43  1  0.883  0.976  0.897  1.0
[/CIF]
.