The compound described by Mn4SiO7 is Ilmenite-like structured and crystallizes in the hexagonal P6_3 space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to six equivalent O(2) atoms to form a mixture of corner, edge, and face-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 42-44°. In the second Mn site, Mn(2) is bonded to one O(1), two equivalent O(2), and three equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with six equivalent Mn(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and  an edgeedge with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-61°. Si(1) is bonded to one O(1) and three equivalent O(3) atoms to form SiO4 tetrahedra that share corners with six equivalent Mn(2)O6 octahedra and edges with three equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-60°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to three equivalent Mn(2) and one Si(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mn(1) and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Mn(2) and one Si(1) atom. is represented by the CIF file [CIF]
data_Mn4SiO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.940
_cell_length_b   8.128
_cell_length_c   8.128
_cell_angle_alpha   60.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   282.647
_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  0.511  0.000  0.000  1.0
  Mn  Mn1  1  0.003  0.887  0.704  1.0
  Mn  Mn2  1  0.003  0.704  0.409  1.0
  Mn  Mn3  1  0.003  0.409  0.887  1.0
  Mn  Mn4  1  0.011  1.000  1.000  1.0
  Mn  Mn5  1  0.503  0.591  0.113  1.0
  Mn  Mn6  1  0.503  0.296  0.591  1.0
  Mn  Mn7  1  0.503  0.113  0.296  1.0
  Si  Si8  1  0.938  0.333  0.333  1.0
  Si  Si9  1  0.438  0.667  0.667  1.0
  O  O10  1  0.771  0.667  0.667  1.0
  O  O11  1  0.271  0.333  0.333  1.0
  O  O12  1  0.261  0.795  0.153  1.0
  O  O13  1  0.761  0.847  0.948  1.0
  O  O14  1  0.761  0.948  0.205  1.0
  O  O15  1  0.261  0.052  0.795  1.0
  O  O16  1  0.261  0.153  0.052  1.0
  O  O17  1  0.761  0.205  0.847  1.0
  O  O18  1  0.799  0.494  0.377  1.0
  O  O19  1  0.299  0.623  0.870  1.0
  O  O20  1  0.299  0.870  0.506  1.0
  O  O21  1  0.799  0.130  0.494  1.0
  O  O22  1  0.299  0.506  0.623  1.0
  O  O23  1  0.799  0.377  0.130  1.0
[/CIF]
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The compound described by Mn4SiO7 is Ilmenite-like structured and crystallizes in the hexagonal P6_3 space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to six equivalent O(2) atoms to form a mixture of corner, edge, and face-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 42-44°. In the second Mn site, Mn(2) is bonded to one O(1), two equivalent O(2), and three equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with six equivalent Mn(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, and  an edgeedge with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-61°. Si(1) is bonded to one O(1) and three equivalent O(3) atoms to form SiO4 tetrahedra that share corners with six equivalent Mn(2)O6 octahedra and edges with three equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-60°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to three equivalent Mn(2) and one Si(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mn(1) and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Mn(2) and one Si(1) atom. is represented by the CIF file [CIF]
data_Mn4SiO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.940
_cell_length_b   8.128
_cell_length_c   8.128
_cell_angle_alpha   60.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   282.647
_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  0.511  0.000  0.000  1.0
  Mn  Mn1  1  0.003  0.887  0.704  1.0
  Mn  Mn2  1  0.003  0.704  0.409  1.0
  Mn  Mn3  1  0.003  0.409  0.887  1.0
  Mn  Mn4  1  0.011  1.000  1.000  1.0
  Mn  Mn5  1  0.503  0.591  0.113  1.0
  Mn  Mn6  1  0.503  0.296  0.591  1.0
  Mn  Mn7  1  0.503  0.113  0.296  1.0
  Si  Si8  1  0.938  0.333  0.333  1.0
  Si  Si9  1  0.438  0.667  0.667  1.0
  O  O10  1  0.771  0.667  0.667  1.0
  O  O11  1  0.271  0.333  0.333  1.0
  O  O12  1  0.261  0.795  0.153  1.0
  O  O13  1  0.761  0.847  0.948  1.0
  O  O14  1  0.761  0.948  0.205  1.0
  O  O15  1  0.261  0.052  0.795  1.0
  O  O16  1  0.261  0.153  0.052  1.0
  O  O17  1  0.761  0.205  0.847  1.0
  O  O18  1  0.799  0.494  0.377  1.0
  O  O19  1  0.299  0.623  0.870  1.0
  O  O20  1  0.299  0.870  0.506  1.0
  O  O21  1  0.799  0.130  0.494  1.0
  O  O22  1  0.299  0.506  0.623  1.0
  O  O23  1  0.799  0.377  0.130  1.0
[/CIF]
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