The crystal structure described by Mn4As3 crystallizes in the monoclinic C2/m space group. There are five inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one As(1), two equivalent As(2), and three equivalent As(3) atoms to form MnAs6 octahedra that share corners with four equivalent Mn(5)As6 octahedra, corners with six equivalent Mn(3)As5 square pyramids, corners with two equivalent Mn(2)As5 trigonal bipyramids, edges with four equivalent Mn(1)As6 octahedra, edges with three equivalent Mn(2)As5 trigonal bipyramids,  a faceface with one Mn(5)As6 octahedra, and  a faceface with one Mn(3)As5 square pyramid. The corner-sharing octahedral tilt angles range from 49-53°. In the second Mn site, Mn(2) is bonded to two equivalent As(1) and three equivalent As(2) atoms to form distorted MnAs5 trigonal bipyramids that share corners with two equivalent Mn(1)As6 octahedra, corners with two equivalent Mn(5)As6 octahedra, corners with six equivalent Mn(3)As5 square pyramids, edges with three equivalent Mn(1)As6 octahedra, edges with two equivalent Mn(3)As5 square pyramids, and edges with four equivalent Mn(2)As5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 21-49°. In the third Mn site, Mn(3) is bonded to one As(3), two equivalent As(1), and two equivalent As(2) atoms to form distorted MnAs5 square pyramids that share corners with six equivalent Mn(1)As6 octahedra, corners with six equivalent Mn(2)As5 trigonal bipyramids, edges with two equivalent Mn(5)As6 octahedra, edges with two equivalent Mn(3)As5 square pyramids, edges with two equivalent Mn(2)As5 trigonal bipyramids, and  a faceface with one Mn(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 46-55°. In the fourth Mn site, Mn(4) is bonded in a distorted square co-planar geometry to two equivalent As(1) and two equivalent As(2) atoms. In the fifth Mn site, Mn(5) is bonded to two equivalent As(1) and four equivalent As(3) atoms to form MnAs6 octahedra that share corners with eight equivalent Mn(1)As6 octahedra, corners with four equivalent Mn(2)As5 trigonal bipyramids, edges with two equivalent Mn(5)As6 octahedra, edges with four equivalent Mn(3)As5 square pyramids, and faces with two equivalent Mn(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 49-53°. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 7-coordinate geometry to one Mn(1), one Mn(4), one Mn(5), two equivalent Mn(2), and two equivalent Mn(3) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to one Mn(4), two equivalent Mn(1), two equivalent Mn(3), and three equivalent Mn(2) atoms. In the third As site, As(3) is bonded in a 6-coordinate geometry to one Mn(3), two equivalent Mn(5), and three equivalent Mn(1) atoms. is represented by the CIF file [CIF]
data_Mn4As3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.741
_cell_length_b   6.741
_cell_length_c   9.400
_cell_angle_alpha   76.646
_cell_angle_beta   76.646
_cell_angle_gamma   30.401
_symmetry_Int_Tables_number   1
_cell_volume   209.856
_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
  Mn  Mn0  1  0.783  0.783  0.166  1.0
  Mn  Mn1  1  0.217  0.217  0.834  1.0
  Mn  Mn2  1  0.657  0.657  0.550  1.0
  Mn  Mn3  1  0.343  0.343  0.450  1.0
  Mn  Mn4  1  0.568  0.568  0.288  1.0
  Mn  Mn5  1  0.432  0.432  0.712  1.0
  Mn  Mn6  1  0.000  0.000  0.500  1.0
  Mn  Mn7  1  0.000  0.000  0.000  1.0
  As  As8  1  0.938  0.938  0.273  1.0
  As  As9  1  0.062  0.062  0.727  1.0
  As  As10  1  0.813  0.813  0.653  1.0
  As  As11  1  0.187  0.187  0.347  1.0
  As  As12  1  0.638  0.638  0.021  1.0
  As  As13  1  0.362  0.362  0.979  1.0
[/CIF]
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The crystal structure described by Mn4As3 crystallizes in the monoclinic C2/m space group. There are five inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one As(1), two equivalent As(2), and three equivalent As(3) atoms to form MnAs6 octahedra that share corners with four equivalent Mn(5)As6 octahedra, corners with six equivalent Mn(3)As5 square pyramids, corners with two equivalent Mn(2)As5 trigonal bipyramids, edges with four equivalent Mn(1)As6 octahedra, edges with three equivalent Mn(2)As5 trigonal bipyramids,  a faceface with one Mn(5)As6 octahedra, and  a faceface with one Mn(3)As5 square pyramid. The corner-sharing octahedral tilt angles range from 49-53°. In the second Mn site, Mn(2) is bonded to two equivalent As(1) and three equivalent As(2) atoms to form distorted MnAs5 trigonal bipyramids that share corners with two equivalent Mn(1)As6 octahedra, corners with two equivalent Mn(5)As6 octahedra, corners with six equivalent Mn(3)As5 square pyramids, edges with three equivalent Mn(1)As6 octahedra, edges with two equivalent Mn(3)As5 square pyramids, and edges with four equivalent Mn(2)As5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 21-49°. In the third Mn site, Mn(3) is bonded to one As(3), two equivalent As(1), and two equivalent As(2) atoms to form distorted MnAs5 square pyramids that share corners with six equivalent Mn(1)As6 octahedra, corners with six equivalent Mn(2)As5 trigonal bipyramids, edges with two equivalent Mn(5)As6 octahedra, edges with two equivalent Mn(3)As5 square pyramids, edges with two equivalent Mn(2)As5 trigonal bipyramids, and  a faceface with one Mn(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 46-55°. In the fourth Mn site, Mn(4) is bonded in a distorted square co-planar geometry to two equivalent As(1) and two equivalent As(2) atoms. In the fifth Mn site, Mn(5) is bonded to two equivalent As(1) and four equivalent As(3) atoms to form MnAs6 octahedra that share corners with eight equivalent Mn(1)As6 octahedra, corners with four equivalent Mn(2)As5 trigonal bipyramids, edges with two equivalent Mn(5)As6 octahedra, edges with four equivalent Mn(3)As5 square pyramids, and faces with two equivalent Mn(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 49-53°. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 7-coordinate geometry to one Mn(1), one Mn(4), one Mn(5), two equivalent Mn(2), and two equivalent Mn(3) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to one Mn(4), two equivalent Mn(1), two equivalent Mn(3), and three equivalent Mn(2) atoms. In the third As site, As(3) is bonded in a 6-coordinate geometry to one Mn(3), two equivalent Mn(5), and three equivalent Mn(1) atoms. is represented by the CIF file [CIF]
data_Mn4As3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.741
_cell_length_b   6.741
_cell_length_c   9.400
_cell_angle_alpha   76.646
_cell_angle_beta   76.646
_cell_angle_gamma   30.401
_symmetry_Int_Tables_number   1
_cell_volume   209.856
_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
  Mn  Mn0  1  0.783  0.783  0.166  1.0
  Mn  Mn1  1  0.217  0.217  0.834  1.0
  Mn  Mn2  1  0.657  0.657  0.550  1.0
  Mn  Mn3  1  0.343  0.343  0.450  1.0
  Mn  Mn4  1  0.568  0.568  0.288  1.0
  Mn  Mn5  1  0.432  0.432  0.712  1.0
  Mn  Mn6  1  0.000  0.000  0.500  1.0
  Mn  Mn7  1  0.000  0.000  0.000  1.0
  As  As8  1  0.938  0.938  0.273  1.0
  As  As9  1  0.062  0.062  0.727  1.0
  As  As10  1  0.813  0.813  0.653  1.0
  As  As11  1  0.187  0.187  0.347  1.0
  As  As12  1  0.638  0.638  0.021  1.0
  As  As13  1  0.362  0.362  0.979  1.0
[/CIF]
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