The material described by MgMn4(Si4O11)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(1), one O(19), one O(3), one O(6), and one O(9) 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 in a 6-coordinate geometry to one O(11), one O(16), one O(3), one O(7), one O(8), and one O(9) atom. In the third Mn site, Mn(3) is bonded to one O(12), one O(14), one O(15), one O(20), and one O(7) atom to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, and  a cornercorner with one Si(8)O4 tetrahedra. In the fourth Mn site, Mn(4) is bonded in a 6-coordinate geometry to one O(11), one O(12), one O(14), one O(15), one O(16), and one O(22) atom. 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 corner-sharing SiO4 tetrahedra. 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 corner-sharing SiO4 tetrahedra. 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 SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra, and  a cornercorner with one Mn(3)O5 trigonal bipyramid. 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 Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, and  a cornercorner with one Mn(3)O5 trigonal bipyramid. 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 Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Mn(3)O5 trigonal bipyramid. 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 corner-sharing SiO4 tetrahedra. 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 Si(4)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra, and  a cornercorner with one Mn(3)O5 trigonal bipyramid. 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 SiO4 tetrahedra that share  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, and  a cornercorner with one Mn(3)O5 trigonal bipyramid. There are twenty-two inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Mn(1), and one Si(8) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Si(1) and one Si(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to 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 3-coordinate geometry to one Mg(1), one Si(3), and one Si(5) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), 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 to one Mg(1), one Mn(1), one Mn(2), and one Si(5) atom to form corner-sharing OMgMn2Si trigonal pyramids. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to 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 to one Mn(1), one Mn(3), one Mn(4), and one Si(7) atom to form distorted corner-sharing OMn3Si tetrahedra. In the thirteenth O site, O(13) is bonded in a 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 2-coordinate 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 planar 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 150 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 distorted 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 120 degrees geometry to one Mn(3) and one Si(8) atom. In the twenty-first O site, O(21) is bonded in a bent 120 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 CIF card [CIF]
data_MgMn4(Si4O11)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.759
_cell_length_b   7.710
_cell_length_c   7.155
_cell_angle_alpha   108.681
_cell_angle_beta   102.254
_cell_angle_gamma   97.269
_symmetry_Int_Tables_number   1
_cell_volume   437.285
_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  0.145  0.755  0.151  1.0
  Mn  Mn1  1  0.379  0.654  0.855  1.0
  Mn  Mn2  1  0.401  0.622  0.369  1.0
  Mn  Mn3  1  0.605  0.374  0.649  1.0
  Mn  Mn4  1  0.623  0.377  0.114  1.0
  Si  Si5  1  0.029  0.381  0.227  1.0
  Si  Si6  1  0.242  0.213  0.954  1.0
  Si  Si7  1  0.215  0.228  0.523  1.0
  Si  Si8  1  0.611  0.975  0.780  1.0
  Si  Si9  1  0.398  0.034  0.235  1.0
  Si  Si10  1  0.786  0.772  0.474  1.0
  Si  Si11  1  0.767  0.783  0.046  1.0
  Si  Si12  1  0.959  0.607  0.753  1.0
  O  O13  1  0.140  0.599  0.851  1.0
  O  O14  1  0.063  0.296  0.415  1.0
  O  O15  1  0.153  0.582  0.296  1.0
  O  O16  1  0.084  0.235  0.038  1.0
  O  O17  1  0.185  0.160  0.707  1.0
  O  O18  1  0.246  0.041  0.349  1.0
  O  O19  1  0.376  0.396  0.600  1.0
  O  O20  1  0.453  0.806  0.673  1.0
  O  O21  1  0.402  0.812  0.185  1.0
  O  O22  1  0.315  0.042  0.008  1.0
  O  O23  1  0.391  0.398  0.071  1.0
  O  O24  1  0.630  0.587  0.922  1.0
  O  O25  1  0.700  0.957  1.000  1.0
  O  O26  1  0.580  0.190  0.833  1.0
  O  O27  1  0.552  0.199  0.365  1.0
  O  O28  1  0.638  0.586  0.374  1.0
  O  O29  1  0.730  0.943  0.628  1.0
  O  O30  1  0.827  0.838  0.292  1.0
  O  O31  1  0.932  0.758  0.974  1.0
  O  O32  1  0.824  0.419  0.675  1.0
  O  O33  1  0.944  0.724  0.597  1.0
  O  O34  1  0.847  0.401  0.167  1.0
[/CIF]
.
The material described by MgMn4(Si4O11)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(1), one O(19), one O(3), one O(6), and one O(9) 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 in a 6-coordinate geometry to one O(11), one O(16), one O(3), one O(7), one O(8), and one O(9) atom. In the third Mn site, Mn(3) is bonded to one O(12), one O(14), one O(15), one O(20), and one O(7) atom to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, and  a cornercorner with one Si(8)O4 tetrahedra. In the fourth Mn site, Mn(4) is bonded in a 6-coordinate geometry to one O(11), one O(12), one O(14), one O(15), one O(16), and one O(22) atom. 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 corner-sharing SiO4 tetrahedra. 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 corner-sharing SiO4 tetrahedra. 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 SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra, and  a cornercorner with one Mn(3)O5 trigonal bipyramid. 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 Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, and  a cornercorner with one Mn(3)O5 trigonal bipyramid. 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 Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Mn(3)O5 trigonal bipyramid. 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 corner-sharing SiO4 tetrahedra. 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 Si(4)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra, and  a cornercorner with one Mn(3)O5 trigonal bipyramid. 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 SiO4 tetrahedra that share  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, and  a cornercorner with one Mn(3)O5 trigonal bipyramid. There are twenty-two inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Mn(1), and one Si(8) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Si(1) and one Si(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to 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 3-coordinate geometry to one Mg(1), one Si(3), and one Si(5) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), 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 to one Mg(1), one Mn(1), one Mn(2), and one Si(5) atom to form corner-sharing OMgMn2Si trigonal pyramids. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to 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 to one Mn(1), one Mn(3), one Mn(4), and one Si(7) atom to form distorted corner-sharing OMn3Si tetrahedra. In the thirteenth O site, O(13) is bonded in a 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 2-coordinate 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 planar 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 150 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 distorted 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 120 degrees geometry to one Mn(3) and one Si(8) atom. In the twenty-first O site, O(21) is bonded in a bent 120 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 CIF card [CIF]
data_MgMn4(Si4O11)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.759
_cell_length_b   7.710
_cell_length_c   7.155
_cell_angle_alpha   108.681
_cell_angle_beta   102.254
_cell_angle_gamma   97.269
_symmetry_Int_Tables_number   1
_cell_volume   437.285
_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  0.145  0.755  0.151  1.0
  Mn  Mn1  1  0.379  0.654  0.855  1.0
  Mn  Mn2  1  0.401  0.622  0.369  1.0
  Mn  Mn3  1  0.605  0.374  0.649  1.0
  Mn  Mn4  1  0.623  0.377  0.114  1.0
  Si  Si5  1  0.029  0.381  0.227  1.0
  Si  Si6  1  0.242  0.213  0.954  1.0
  Si  Si7  1  0.215  0.228  0.523  1.0
  Si  Si8  1  0.611  0.975  0.780  1.0
  Si  Si9  1  0.398  0.034  0.235  1.0
  Si  Si10  1  0.786  0.772  0.474  1.0
  Si  Si11  1  0.767  0.783  0.046  1.0
  Si  Si12  1  0.959  0.607  0.753  1.0
  O  O13  1  0.140  0.599  0.851  1.0
  O  O14  1  0.063  0.296  0.415  1.0
  O  O15  1  0.153  0.582  0.296  1.0
  O  O16  1  0.084  0.235  0.038  1.0
  O  O17  1  0.185  0.160  0.707  1.0
  O  O18  1  0.246  0.041  0.349  1.0
  O  O19  1  0.376  0.396  0.600  1.0
  O  O20  1  0.453  0.806  0.673  1.0
  O  O21  1  0.402  0.812  0.185  1.0
  O  O22  1  0.315  0.042  0.008  1.0
  O  O23  1  0.391  0.398  0.071  1.0
  O  O24  1  0.630  0.587  0.922  1.0
  O  O25  1  0.700  0.957  1.000  1.0
  O  O26  1  0.580  0.190  0.833  1.0
  O  O27  1  0.552  0.199  0.365  1.0
  O  O28  1  0.638  0.586  0.374  1.0
  O  O29  1  0.730  0.943  0.628  1.0
  O  O30  1  0.827  0.838  0.292  1.0
  O  O31  1  0.932  0.758  0.974  1.0
  O  O32  1  0.824  0.419  0.675  1.0
  O  O33  1  0.944  0.724  0.597  1.0
  O  O34  1  0.847  0.401  0.167  1.0
[/CIF]
.