The material described by Mn4Si4O13 crystallizes in the triclinic P-1 space group. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 5-coordinate geometry to one O(3), one O(5), one O(6), and two equivalent O(2) atoms. In the second Mn site, Mn(2) is bonded to one O(2), one O(3), one O(4), one O(6), and two equivalent O(1) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, and  an edgeedge with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles are 52°. In the third Mn site, Mn(3) is bonded to one O(10), one O(4), one O(7), one O(9), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, corners with two equivalent Mn(4)O5 trigonal bipyramids,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Si(1)O4 tetrahedra, and  an edgeedge with one Mn(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 52°. In the fourth Mn site, Mn(4) is bonded to one O(10), one O(5), one O(9), and two equivalent O(7) atoms to form distorted MnO5 trigonal bipyramids that share corners with two equivalent Mn(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(4)O4 tetrahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Si(1)O4 tetrahedra, and  an edgeedge with one Mn(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 61-71°. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(3), one O(4), one O(5), and one O(9) atom to form SiO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra, and  an edgeedge with one Mn(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 54-57°. In the second Si site, Si(2) is bonded to one O(10), one O(12), one O(13), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and  a cornercorner with one Mn(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 60-65°. In the third Si site, Si(3) is bonded to one O(1), one O(11), one O(12), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-67°. In the fourth Si site, Si(4) is bonded to one O(11), one O(13), one O(2), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Mn(4)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 54-55°. There are thirteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Mn(2) and one Si(3) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mn(2), two equivalent Mn(1), and one Si(4) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Mn(1), one Mn(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mn(2), one Mn(3), and one Si(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(4), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1), one Mn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded to one Mn(3), two equivalent Mn(4), and one Si(4) atom to form distorted edge-sharing OMn3Si tetrahedra. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to two equivalent Mn(3) and one Si(3) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Mn(3), one Mn(4), and one Si(1) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Mn(3), one Mn(4), and one Si(2) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one Si(2) and one Si(3) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Si(2) and one Si(4) atom. is represented by the CIF card [CIF]
data_Mn4Si4O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.104
_cell_length_b   7.812
_cell_length_c   10.072
_cell_angle_alpha   67.414
_cell_angle_beta   84.139
_cell_angle_gamma   81.332
_symmetry_Int_Tables_number   1
_cell_volume   509.571
_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  0.061  0.198  0.003  1.0
  Mn  Mn1  1  0.563  0.203  0.992  1.0
  Mn  Mn2  1  0.570  0.560  0.621  1.0
  Mn  Mn3  1  0.051  0.574  0.620  1.0
  Mn  Mn4  1  0.949  0.426  0.380  1.0
  Mn  Mn5  1  0.430  0.440  0.379  1.0
  Mn  Mn6  1  0.437  0.797  0.008  1.0
  Mn  Mn7  1  0.939  0.802  0.997  1.0
  Si  Si8  1  0.273  0.578  0.827  1.0
  Si  Si9  1  0.719  0.863  0.714  1.0
  Si  Si10  1  0.389  0.141  0.710  1.0
  Si  Si11  1  0.941  0.165  0.711  1.0
  Si  Si12  1  0.059  0.835  0.289  1.0
  Si  Si13  1  0.611  0.859  0.290  1.0
  Si  Si14  1  0.281  0.137  0.286  1.0
  Si  Si15  1  0.727  0.422  0.173  1.0
  O  O16  1  0.413  0.091  0.881  1.0
  O  O17  1  0.885  0.112  0.883  1.0
  O  O18  1  0.230  0.710  0.922  1.0
  O  O19  1  0.493  0.463  0.840  1.0
  O  O20  1  0.100  0.447  0.840  1.0
  O  O21  1  0.724  0.772  0.891  1.0
  O  O22  1  0.876  0.385  0.604  1.0
  O  O23  1  0.446  0.345  0.600  1.0
  O  O24  1  0.268  0.688  0.650  1.0
  O  O25  1  0.773  0.713  0.637  1.0
  O  O26  1  0.169  0.138  0.687  1.0
  O  O27  1  0.505  0.969  0.668  1.0
  O  O28  1  0.865  0.023  0.652  1.0
  O  O29  1  0.135  0.977  0.348  1.0
  O  O30  1  0.495  0.031  0.332  1.0
  O  O31  1  0.831  0.862  0.313  1.0
  O  O32  1  0.227  0.287  0.363  1.0
  O  O33  1  0.732  0.312  0.350  1.0
  O  O34  1  0.554  0.655  0.400  1.0
  O  O35  1  0.124  0.615  0.396  1.0
  O  O36  1  0.276  0.228  0.109  1.0
  O  O37  1  0.900  0.553  0.160  1.0
  O  O38  1  0.507  0.537  0.160  1.0
  O  O39  1  0.770  0.290  0.078  1.0
  O  O40  1  0.115  0.888  0.117  1.0
  O  O41  1  0.587  0.909  0.119  1.0
[/CIF]
.
The material described by Mn4Si4O13 crystallizes in the triclinic P-1 space group. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 5-coordinate geometry to one O(3), one O(5), one O(6), and two equivalent O(2) atoms. In the second Mn site, Mn(2) is bonded to one O(2), one O(3), one O(4), one O(6), and two equivalent O(1) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, and  an edgeedge with one Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles are 52°. In the third Mn site, Mn(3) is bonded to one O(10), one O(4), one O(7), one O(9), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, corners with two equivalent Mn(4)O5 trigonal bipyramids,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Si(1)O4 tetrahedra, and  an edgeedge with one Mn(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 52°. In the fourth Mn site, Mn(4) is bonded to one O(10), one O(5), one O(9), and two equivalent O(7) atoms to form distorted MnO5 trigonal bipyramids that share corners with two equivalent Mn(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(4)O4 tetrahedra,  an edgeedge with one Mn(3)O6 octahedra,  an edgeedge with one Si(1)O4 tetrahedra, and  an edgeedge with one Mn(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 61-71°. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(3), one O(4), one O(5), and one O(9) atom to form SiO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  an edgeedge with one Mn(3)O6 octahedra, and  an edgeedge with one Mn(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 54-57°. In the second Si site, Si(2) is bonded to one O(10), one O(12), one O(13), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and  a cornercorner with one Mn(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 60-65°. In the third Si site, Si(3) is bonded to one O(1), one O(11), one O(12), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-67°. In the fourth Si site, Si(4) is bonded to one O(11), one O(13), one O(2), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(2)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Mn(4)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 54-55°. There are thirteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Mn(2) and one Si(3) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mn(2), two equivalent Mn(1), and one Si(4) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Mn(1), one Mn(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mn(2), one Mn(3), and one Si(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(4), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1), one Mn(2), and one Si(2) atom. In the seventh O site, O(7) is bonded to one Mn(3), two equivalent Mn(4), and one Si(4) atom to form distorted edge-sharing OMn3Si tetrahedra. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to two equivalent Mn(3) and one Si(3) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Mn(3), one Mn(4), and one Si(1) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Mn(3), one Mn(4), and one Si(2) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one Si(2) and one Si(3) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Si(2) and one Si(4) atom. is represented by the CIF card [CIF]
data_Mn4Si4O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.104
_cell_length_b   7.812
_cell_length_c   10.072
_cell_angle_alpha   67.414
_cell_angle_beta   84.139
_cell_angle_gamma   81.332
_symmetry_Int_Tables_number   1
_cell_volume   509.571
_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  0.061  0.198  0.003  1.0
  Mn  Mn1  1  0.563  0.203  0.992  1.0
  Mn  Mn2  1  0.570  0.560  0.621  1.0
  Mn  Mn3  1  0.051  0.574  0.620  1.0
  Mn  Mn4  1  0.949  0.426  0.380  1.0
  Mn  Mn5  1  0.430  0.440  0.379  1.0
  Mn  Mn6  1  0.437  0.797  0.008  1.0
  Mn  Mn7  1  0.939  0.802  0.997  1.0
  Si  Si8  1  0.273  0.578  0.827  1.0
  Si  Si9  1  0.719  0.863  0.714  1.0
  Si  Si10  1  0.389  0.141  0.710  1.0
  Si  Si11  1  0.941  0.165  0.711  1.0
  Si  Si12  1  0.059  0.835  0.289  1.0
  Si  Si13  1  0.611  0.859  0.290  1.0
  Si  Si14  1  0.281  0.137  0.286  1.0
  Si  Si15  1  0.727  0.422  0.173  1.0
  O  O16  1  0.413  0.091  0.881  1.0
  O  O17  1  0.885  0.112  0.883  1.0
  O  O18  1  0.230  0.710  0.922  1.0
  O  O19  1  0.493  0.463  0.840  1.0
  O  O20  1  0.100  0.447  0.840  1.0
  O  O21  1  0.724  0.772  0.891  1.0
  O  O22  1  0.876  0.385  0.604  1.0
  O  O23  1  0.446  0.345  0.600  1.0
  O  O24  1  0.268  0.688  0.650  1.0
  O  O25  1  0.773  0.713  0.637  1.0
  O  O26  1  0.169  0.138  0.687  1.0
  O  O27  1  0.505  0.969  0.668  1.0
  O  O28  1  0.865  0.023  0.652  1.0
  O  O29  1  0.135  0.977  0.348  1.0
  O  O30  1  0.495  0.031  0.332  1.0
  O  O31  1  0.831  0.862  0.313  1.0
  O  O32  1  0.227  0.287  0.363  1.0
  O  O33  1  0.732  0.312  0.350  1.0
  O  O34  1  0.554  0.655  0.400  1.0
  O  O35  1  0.124  0.615  0.396  1.0
  O  O36  1  0.276  0.228  0.109  1.0
  O  O37  1  0.900  0.553  0.160  1.0
  O  O38  1  0.507  0.537  0.160  1.0
  O  O39  1  0.770  0.290  0.078  1.0
  O  O40  1  0.115  0.888  0.117  1.0
  O  O41  1  0.587  0.909  0.119  1.0
[/CIF]
.