The material described by Mg4Ti3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent Mg(2), four equivalent Mg(1), and five equivalent Ti(1) atoms to form distorted MgMg7Ti5 cuboctahedra that share corners with three equivalent Mg(2)Mg9Ti3 cuboctahedra, corners with six equivalent Mg(1)Mg7Ti5 cuboctahedra, corners with nine equivalent Ti(1)Mg6Ti6 cuboctahedra,  an edgeedge with one Mg(2)Mg9Ti3 cuboctahedra, edges with six equivalent Mg(1)Mg7Ti5 cuboctahedra, edges with eleven equivalent Ti(1)Mg6Ti6 cuboctahedra, faces with three equivalent Mg(2)Mg9Ti3 cuboctahedra, faces with seven equivalent Ti(1)Mg6Ti6 cuboctahedra, and faces with ten equivalent Mg(1)Mg7Ti5 cuboctahedra. In the second Mg site, Mg(2) is bonded to nine equivalent Mg(1) and three equivalent Ti(1) atoms to form MgMg9Ti3 cuboctahedra that share corners with nine equivalent Mg(1)Mg7Ti5 cuboctahedra, corners with nine equivalent Ti(1)Mg6Ti6 cuboctahedra, edges with three equivalent Mg(1)Mg7Ti5 cuboctahedra, edges with six equivalent Mg(2)Mg9Ti3 cuboctahedra, edges with nine equivalent Ti(1)Mg6Ti6 cuboctahedra, faces with two equivalent Mg(2)Mg9Ti3 cuboctahedra, faces with nine equivalent Mg(1)Mg7Ti5 cuboctahedra, and faces with nine equivalent Ti(1)Mg6Ti6 cuboctahedra. Ti(1) is bonded to one Mg(2), five equivalent Mg(1), and six equivalent Ti(1) atoms to form TiMg6Ti6 cuboctahedra that share corners with three equivalent Mg(2)Mg9Ti3 cuboctahedra, corners with six equivalent Ti(1)Mg6Ti6 cuboctahedra, corners with nine equivalent Mg(1)Mg7Ti5 cuboctahedra, edges with three equivalent Mg(2)Mg9Ti3 cuboctahedra, edges with four equivalent Ti(1)Mg6Ti6 cuboctahedra, edges with eleven equivalent Mg(1)Mg7Ti5 cuboctahedra, faces with three equivalent Mg(2)Mg9Ti3 cuboctahedra, faces with seven equivalent Mg(1)Mg7Ti5 cuboctahedra, and faces with ten equivalent Ti(1)Mg6Ti6 cuboctahedra. is represented by the CIF card [CIF]
data_Mg4Ti3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.194
_cell_length_b   8.194
_cell_length_c   4.884
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   284.002
_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  0.626  0.537  0.750  1.0
  Mg  Mg1  1  0.374  0.463  0.250  1.0
  Mg  Mg2  1  0.333  0.667  0.750  1.0
  Mg  Mg3  1  0.537  0.911  0.250  1.0
  Mg  Mg4  1  0.911  0.374  0.750  1.0
  Mg  Mg5  1  0.089  0.626  0.250  1.0
  Mg  Mg6  1  0.463  0.089  0.750  1.0
  Mg  Mg7  1  0.667  0.333  0.250  1.0
  Ti  Ti8  1  0.829  0.788  0.250  1.0
  Ti  Ti9  1  0.171  0.212  0.750  1.0
  Ti  Ti10  1  0.788  0.959  0.750  1.0
  Ti  Ti11  1  0.959  0.171  0.250  1.0
  Ti  Ti12  1  0.041  0.829  0.750  1.0
  Ti  Ti13  1  0.212  0.041  0.250  1.0
[/CIF]
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The material described by Mg4Ti3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent Mg(2), four equivalent Mg(1), and five equivalent Ti(1) atoms to form distorted MgMg7Ti5 cuboctahedra that share corners with three equivalent Mg(2)Mg9Ti3 cuboctahedra, corners with six equivalent Mg(1)Mg7Ti5 cuboctahedra, corners with nine equivalent Ti(1)Mg6Ti6 cuboctahedra,  an edgeedge with one Mg(2)Mg9Ti3 cuboctahedra, edges with six equivalent Mg(1)Mg7Ti5 cuboctahedra, edges with eleven equivalent Ti(1)Mg6Ti6 cuboctahedra, faces with three equivalent Mg(2)Mg9Ti3 cuboctahedra, faces with seven equivalent Ti(1)Mg6Ti6 cuboctahedra, and faces with ten equivalent Mg(1)Mg7Ti5 cuboctahedra. In the second Mg site, Mg(2) is bonded to nine equivalent Mg(1) and three equivalent Ti(1) atoms to form MgMg9Ti3 cuboctahedra that share corners with nine equivalent Mg(1)Mg7Ti5 cuboctahedra, corners with nine equivalent Ti(1)Mg6Ti6 cuboctahedra, edges with three equivalent Mg(1)Mg7Ti5 cuboctahedra, edges with six equivalent Mg(2)Mg9Ti3 cuboctahedra, edges with nine equivalent Ti(1)Mg6Ti6 cuboctahedra, faces with two equivalent Mg(2)Mg9Ti3 cuboctahedra, faces with nine equivalent Mg(1)Mg7Ti5 cuboctahedra, and faces with nine equivalent Ti(1)Mg6Ti6 cuboctahedra. Ti(1) is bonded to one Mg(2), five equivalent Mg(1), and six equivalent Ti(1) atoms to form TiMg6Ti6 cuboctahedra that share corners with three equivalent Mg(2)Mg9Ti3 cuboctahedra, corners with six equivalent Ti(1)Mg6Ti6 cuboctahedra, corners with nine equivalent Mg(1)Mg7Ti5 cuboctahedra, edges with three equivalent Mg(2)Mg9Ti3 cuboctahedra, edges with four equivalent Ti(1)Mg6Ti6 cuboctahedra, edges with eleven equivalent Mg(1)Mg7Ti5 cuboctahedra, faces with three equivalent Mg(2)Mg9Ti3 cuboctahedra, faces with seven equivalent Mg(1)Mg7Ti5 cuboctahedra, and faces with ten equivalent Ti(1)Mg6Ti6 cuboctahedra. is represented by the CIF card [CIF]
data_Mg4Ti3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.194
_cell_length_b   8.194
_cell_length_c   4.884
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   284.002
_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  0.626  0.537  0.750  1.0
  Mg  Mg1  1  0.374  0.463  0.250  1.0
  Mg  Mg2  1  0.333  0.667  0.750  1.0
  Mg  Mg3  1  0.537  0.911  0.250  1.0
  Mg  Mg4  1  0.911  0.374  0.750  1.0
  Mg  Mg5  1  0.089  0.626  0.250  1.0
  Mg  Mg6  1  0.463  0.089  0.750  1.0
  Mg  Mg7  1  0.667  0.333  0.250  1.0
  Ti  Ti8  1  0.829  0.788  0.250  1.0
  Ti  Ti9  1  0.171  0.212  0.750  1.0
  Ti  Ti10  1  0.788  0.959  0.750  1.0
  Ti  Ti11  1  0.959  0.171  0.250  1.0
  Ti  Ti12  1  0.041  0.829  0.750  1.0
  Ti  Ti13  1  0.212  0.041  0.250  1.0
[/CIF]
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