The structure described by MgMn4(Si4O11)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(10), one O(19), one O(2), one O(4), and one O(6) atom. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 5-coordinate geometry to one O(1), one O(12), one O(7), one O(8), and one O(9) atom. In the second Mn site, Mn(2) is bonded to one O(11), one O(16), one O(3), one O(8), and one O(9) atom to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra, and  an edgeedge with one Mn(4)O6 octahedra. In the third Mn site, Mn(3) is bonded in a 5-coordinate geometry to one O(12), one O(14), one O(15), one O(20), and one O(7) atom. In the fourth Mn site, Mn(4) is bonded to one O(11), one O(12), one O(14), one O(15), one O(16), and one O(22) atom to form distorted MnO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, and  an edgeedge with one Mn(2)O5 trigonal bipyramid. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(22), one O(3), and one O(4) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Mn(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 10°. In the second Si site, Si(2) is bonded to one O(10), one O(11), one O(4), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra, and  a cornercorner with one Mn(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 55°. In the third Si site, Si(3) is bonded to one O(2), one O(5), one O(6), and one O(7) atom to form corner-sharing SiO4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(13), one O(14), one O(17), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, and  a cornercorner with one Mn(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 51°. In the fifth Si site, Si(5) is bonded to one O(10), one O(15), one O(6), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Mn(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 65°. In the sixth Si site, Si(6) is bonded to one O(16), one O(17), one O(18), and one O(21) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra, and  a cornercorner with one Mn(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 58°. In the seventh Si site, Si(7) is bonded to one O(12), one O(13), one O(18), and one O(19) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra, and  a cornercorner with one Si(8)O4 tetrahedra. The corner-sharing octahedral tilt angles are 69°. In the eighth Si site, Si(8) is bonded to one O(1), one O(19), one O(20), and one O(21) atom to form corner-sharing SiO4 tetrahedra. There are twenty-two inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Mn(1) and one Si(8) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Si(1), and one Si(3) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mn(2) and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Si(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Mg(1), one Si(3), and one Si(5) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(3), and one Si(3) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Mn(1), one Mn(2), and one Si(4) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(2), and one Si(5) atom. In the tenth O site, O(10) is bonded in a distorted T-shaped geometry to one Mg(1), one Si(2), and one Si(5) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Mn(2), one Mn(4), and one Si(2) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Mn(1), one Mn(3), one Mn(4), and one Si(7) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 120 degrees geometry to one Si(4) and one Si(7) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal planar geometry to one Mn(3), one Mn(4), and one Si(4) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Mn(3), one Mn(4), and one Si(5) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal non-coplanar geometry to one Mn(2), one Mn(4), and one Si(6) atom. In the seventeenth O site, O(17) is bonded in a bent 120 degrees geometry to one Si(4) and one Si(6) atom. In the eighteenth O site, O(18) is bonded in a bent 150 degrees geometry to one Si(6) and one Si(7) atom. In the nineteenth O site, O(19) is bonded in a trigonal planar geometry to one Mg(1), one Si(7), and one Si(8) atom. In the twentieth O site, O(20) is bonded in a distorted bent 150 degrees geometry to one Mn(3) and one Si(8) atom. In the twenty-first O site, O(21) is bonded in a distorted bent 150 degrees geometry to one Si(6) and one Si(8) atom. In the twenty-second O site, O(22) is bonded in a linear geometry to one Mn(4) and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn4(Si4O11)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.727
_cell_length_b   7.742
_cell_length_c   7.162
_cell_angle_alpha   108.725
_cell_angle_beta   103.808
_cell_angle_gamma   95.513
_symmetry_Int_Tables_number   1
_cell_volume   437.130
_cell_formula_units_Z   1
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  0.062  0.011  0.117  1.0
  Mn  Mn1  1  0.373  0.660  0.847  1.0
  Mn  Mn2  1  0.388  0.657  0.353  1.0
  Mn  Mn3  1  0.606  0.376  0.645  1.0
  Mn  Mn4  1  0.617  0.379  0.128  1.0
  Si  Si5  1  0.027  0.395  0.235  1.0
  Si  Si6  1  0.234  0.229  0.953  1.0
  Si  Si7  1  0.224  0.229  0.532  1.0
  Si  Si8  1  0.614  0.979  0.783  1.0
  Si  Si9  1  0.403  0.032  0.236  1.0
  Si  Si10  1  0.778  0.774  0.476  1.0
  Si  Si11  1  0.769  0.767  0.045  1.0
  Si  Si12  1  0.965  0.600  0.759  1.0
  O  O13  1  0.142  0.558  0.800  1.0
  O  O14  1  0.060  0.249  0.372  1.0
  O  O15  1  0.158  0.579  0.325  1.0
  O  O16  1  0.065  0.242  0.023  1.0
  O  O17  1  0.180  0.159  0.705  1.0
  O  O18  1  0.265  0.041  0.367  1.0
  O  O19  1  0.377  0.397  0.609  1.0
  O  O20  1  0.456  0.816  0.682  1.0
  O  O21  1  0.436  0.824  0.171  1.0
  O  O22  1  0.279  0.046  0.021  1.0
  O  O23  1  0.383  0.401  0.073  1.0
  O  O24  1  0.630  0.583  0.917  1.0
  O  O25  1  0.727  0.953  0.993  1.0
  O  O26  1  0.580  0.192  0.849  1.0
  O  O27  1  0.550  0.208  0.350  1.0
  O  O28  1  0.629  0.594  0.379  1.0
  O  O29  1  0.720  0.953  0.617  1.0
  O  O30  1  0.825  0.831  0.293  1.0
  O  O31  1  0.943  0.750  0.986  1.0
  O  O32  1  0.825  0.418  0.680  1.0
  O  O33  1  0.935  0.732  0.618  1.0
  O  O34  1  0.842  0.409  0.188  1.0
[/CIF]
.
The structure described by MgMn4(Si4O11)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(10), one O(19), one O(2), one O(4), and one O(6) atom. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 5-coordinate geometry to one O(1), one O(12), one O(7), one O(8), and one O(9) atom. In the second Mn site, Mn(2) is bonded to one O(11), one O(16), one O(3), one O(8), and one O(9) atom to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra, and  an edgeedge with one Mn(4)O6 octahedra. In the third Mn site, Mn(3) is bonded in a 5-coordinate geometry to one O(12), one O(14), one O(15), one O(20), and one O(7) atom. In the fourth Mn site, Mn(4) is bonded to one O(11), one O(12), one O(14), one O(15), one O(16), and one O(22) atom to form distorted MnO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, and  an edgeedge with one Mn(2)O5 trigonal bipyramid. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(22), one O(3), and one O(4) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Mn(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 10°. In the second Si site, Si(2) is bonded to one O(10), one O(11), one O(4), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra, and  a cornercorner with one Mn(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 55°. In the third Si site, Si(3) is bonded to one O(2), one O(5), one O(6), and one O(7) atom to form corner-sharing SiO4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(13), one O(14), one O(17), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, and  a cornercorner with one Mn(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 51°. In the fifth Si site, Si(5) is bonded to one O(10), one O(15), one O(6), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Mn(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 65°. In the sixth Si site, Si(6) is bonded to one O(16), one O(17), one O(18), and one O(21) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra, and  a cornercorner with one Mn(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 58°. In the seventh Si site, Si(7) is bonded to one O(12), one O(13), one O(18), and one O(19) atom to form SiO4 tetrahedra that share  a cornercorner with one Mn(4)O6 octahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra, and  a cornercorner with one Si(8)O4 tetrahedra. The corner-sharing octahedral tilt angles are 69°. In the eighth Si site, Si(8) is bonded to one O(1), one O(19), one O(20), and one O(21) atom to form corner-sharing SiO4 tetrahedra. There are twenty-two inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Mn(1) and one Si(8) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Si(1), and one Si(3) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mn(2) and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Si(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Mg(1), one Si(3), and one Si(5) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(3), and one Si(3) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Mn(1), one Mn(2), and one Si(4) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(2), and one Si(5) atom. In the tenth O site, O(10) is bonded in a distorted T-shaped geometry to one Mg(1), one Si(2), and one Si(5) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Mn(2), one Mn(4), and one Si(2) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Mn(1), one Mn(3), one Mn(4), and one Si(7) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 120 degrees geometry to one Si(4) and one Si(7) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal planar geometry to one Mn(3), one Mn(4), and one Si(4) atom. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Mn(3), one Mn(4), and one Si(5) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal non-coplanar geometry to one Mn(2), one Mn(4), and one Si(6) atom. In the seventeenth O site, O(17) is bonded in a bent 120 degrees geometry to one Si(4) and one Si(6) atom. In the eighteenth O site, O(18) is bonded in a bent 150 degrees geometry to one Si(6) and one Si(7) atom. In the nineteenth O site, O(19) is bonded in a trigonal planar geometry to one Mg(1), one Si(7), and one Si(8) atom. In the twentieth O site, O(20) is bonded in a distorted bent 150 degrees geometry to one Mn(3) and one Si(8) atom. In the twenty-first O site, O(21) is bonded in a distorted bent 150 degrees geometry to one Si(6) and one Si(8) atom. In the twenty-second O site, O(22) is bonded in a linear geometry to one Mn(4) and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn4(Si4O11)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.727
_cell_length_b   7.742
_cell_length_c   7.162
_cell_angle_alpha   108.725
_cell_angle_beta   103.808
_cell_angle_gamma   95.513
_symmetry_Int_Tables_number   1
_cell_volume   437.130
_cell_formula_units_Z   1
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  0.062  0.011  0.117  1.0
  Mn  Mn1  1  0.373  0.660  0.847  1.0
  Mn  Mn2  1  0.388  0.657  0.353  1.0
  Mn  Mn3  1  0.606  0.376  0.645  1.0
  Mn  Mn4  1  0.617  0.379  0.128  1.0
  Si  Si5  1  0.027  0.395  0.235  1.0
  Si  Si6  1  0.234  0.229  0.953  1.0
  Si  Si7  1  0.224  0.229  0.532  1.0
  Si  Si8  1  0.614  0.979  0.783  1.0
  Si  Si9  1  0.403  0.032  0.236  1.0
  Si  Si10  1  0.778  0.774  0.476  1.0
  Si  Si11  1  0.769  0.767  0.045  1.0
  Si  Si12  1  0.965  0.600  0.759  1.0
  O  O13  1  0.142  0.558  0.800  1.0
  O  O14  1  0.060  0.249  0.372  1.0
  O  O15  1  0.158  0.579  0.325  1.0
  O  O16  1  0.065  0.242  0.023  1.0
  O  O17  1  0.180  0.159  0.705  1.0
  O  O18  1  0.265  0.041  0.367  1.0
  O  O19  1  0.377  0.397  0.609  1.0
  O  O20  1  0.456  0.816  0.682  1.0
  O  O21  1  0.436  0.824  0.171  1.0
  O  O22  1  0.279  0.046  0.021  1.0
  O  O23  1  0.383  0.401  0.073  1.0
  O  O24  1  0.630  0.583  0.917  1.0
  O  O25  1  0.727  0.953  0.993  1.0
  O  O26  1  0.580  0.192  0.849  1.0
  O  O27  1  0.550  0.208  0.350  1.0
  O  O28  1  0.629  0.594  0.379  1.0
  O  O29  1  0.720  0.953  0.617  1.0
  O  O30  1  0.825  0.831  0.293  1.0
  O  O31  1  0.943  0.750  0.986  1.0
  O  O32  1  0.825  0.418  0.680  1.0
  O  O33  1  0.935  0.732  0.618  1.0
  O  O34  1  0.842  0.409  0.188  1.0
[/CIF]
.