The crystal structure described by Mn20Si12C crystallizes in the monoclinic P2/m space group. There are eight inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(3), and two equivalent Si(4) atoms. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to two equivalent Si(2), two equivalent Si(3), and two equivalent Si(4) atoms. In the third Mn site, Mn(3) is bonded in a 6-coordinate geometry to two equivalent Si(2), two equivalent Si(3), and two equivalent Si(4) atoms. In the fourth Mn site, Mn(4) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(3), and two equivalent Si(4) atoms. In the fifth Mn site, Mn(5) is bonded in a 5-coordinate geometry to two equivalent Si(4) and three equivalent Si(1) atoms. In the sixth Mn site, Mn(6) is bonded in a distorted single-bond geometry to two equivalent Si(3), three equivalent Si(2), and one C(1) atom. In the seventh Mn site, Mn(7) is bonded in a 5-coordinate geometry to one Si(1), one Si(3), and three equivalent Si(4) atoms. In the eighth Mn site, Mn(8) is bonded in a distorted single-bond geometry to one Si(2), one Si(4), three equivalent Si(3), and one C(1) atom. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Mn(1), two equivalent Mn(4), two equivalent Mn(7), and three equivalent Mn(5) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Mn(2), two equivalent Mn(3), two equivalent Mn(8), and three equivalent Mn(6) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to one Mn(1), one Mn(2), one Mn(3), one Mn(4), one Mn(6), one Mn(7), and three equivalent Mn(8) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to one Mn(1), one Mn(2), one Mn(3), one Mn(4), one Mn(5), one Mn(8), and three equivalent Mn(7) atoms. C(1) is bonded in an octahedral geometry to two equivalent Mn(6) and four equivalent Mn(8) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mn20Si12C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.916
_cell_length_b   4.802
_cell_length_c   6.867
_cell_angle_alpha   89.941
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   392.911
_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
  Mn  Mn0  1  0.332  0.500  0.000  1.0
  Mn  Mn1  1  0.835  0.500  0.500  1.0
  Mn  Mn2  1  0.165  0.500  0.500  1.0
  Mn  Mn3  1  0.668  0.500  0.000  1.0
  Mn  Mn4  1  0.167  0.000  0.500  1.0
  Mn  Mn5  1  0.666  0.000  0.000  1.0
  Mn  Mn6  1  0.334  0.000  0.000  1.0
  Mn  Mn7  1  0.833  0.000  0.500  1.0
  Mn  Mn8  1  0.500  0.252  0.744  1.0
  Mn  Mn9  1  0.000  0.258  0.238  1.0
  Mn  Mn10  1  0.377  0.251  0.377  1.0
  Mn  Mn11  1  0.881  0.260  0.881  1.0
  Mn  Mn12  1  0.119  0.260  0.881  1.0
  Mn  Mn13  1  0.623  0.251  0.377  1.0
  Mn  Mn14  1  0.500  0.748  0.256  1.0
  Mn  Mn15  1  0.000  0.742  0.762  1.0
  Mn  Mn16  1  0.119  0.740  0.119  1.0
  Mn  Mn17  1  0.623  0.749  0.623  1.0
  Mn  Mn18  1  0.377  0.749  0.623  1.0
  Mn  Mn19  1  0.881  0.740  0.119  1.0
  Si  Si20  1  0.500  0.250  0.103  1.0
  Si  Si21  1  0.000  0.239  0.597  1.0
  Si  Si22  1  0.200  0.238  0.200  1.0
  Si  Si23  1  0.700  0.249  0.700  1.0
  Si  Si24  1  0.300  0.249  0.700  1.0
  Si  Si25  1  0.800  0.238  0.200  1.0
  Si  Si26  1  0.500  0.750  0.897  1.0
  Si  Si27  1  0.000  0.761  0.403  1.0
  Si  Si28  1  0.300  0.751  0.300  1.0
  Si  Si29  1  0.800  0.762  0.800  1.0
  Si  Si30  1  0.200  0.762  0.800  1.0
  Si  Si31  1  0.700  0.751  0.300  1.0
  C  C32  1  0.000  0.500  0.000  1.0
[/CIF]
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The crystal structure described by Mn20Si12C crystallizes in the monoclinic P2/m space group. There are eight inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(3), and two equivalent Si(4) atoms. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to two equivalent Si(2), two equivalent Si(3), and two equivalent Si(4) atoms. In the third Mn site, Mn(3) is bonded in a 6-coordinate geometry to two equivalent Si(2), two equivalent Si(3), and two equivalent Si(4) atoms. In the fourth Mn site, Mn(4) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(3), and two equivalent Si(4) atoms. In the fifth Mn site, Mn(5) is bonded in a 5-coordinate geometry to two equivalent Si(4) and three equivalent Si(1) atoms. In the sixth Mn site, Mn(6) is bonded in a distorted single-bond geometry to two equivalent Si(3), three equivalent Si(2), and one C(1) atom. In the seventh Mn site, Mn(7) is bonded in a 5-coordinate geometry to one Si(1), one Si(3), and three equivalent Si(4) atoms. In the eighth Mn site, Mn(8) is bonded in a distorted single-bond geometry to one Si(2), one Si(4), three equivalent Si(3), and one C(1) atom. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Mn(1), two equivalent Mn(4), two equivalent Mn(7), and three equivalent Mn(5) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Mn(2), two equivalent Mn(3), two equivalent Mn(8), and three equivalent Mn(6) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to one Mn(1), one Mn(2), one Mn(3), one Mn(4), one Mn(6), one Mn(7), and three equivalent Mn(8) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to one Mn(1), one Mn(2), one Mn(3), one Mn(4), one Mn(5), one Mn(8), and three equivalent Mn(7) atoms. C(1) is bonded in an octahedral geometry to two equivalent Mn(6) and four equivalent Mn(8) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mn20Si12C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.916
_cell_length_b   4.802
_cell_length_c   6.867
_cell_angle_alpha   89.941
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   392.911
_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
  Mn  Mn0  1  0.332  0.500  0.000  1.0
  Mn  Mn1  1  0.835  0.500  0.500  1.0
  Mn  Mn2  1  0.165  0.500  0.500  1.0
  Mn  Mn3  1  0.668  0.500  0.000  1.0
  Mn  Mn4  1  0.167  0.000  0.500  1.0
  Mn  Mn5  1  0.666  0.000  0.000  1.0
  Mn  Mn6  1  0.334  0.000  0.000  1.0
  Mn  Mn7  1  0.833  0.000  0.500  1.0
  Mn  Mn8  1  0.500  0.252  0.744  1.0
  Mn  Mn9  1  0.000  0.258  0.238  1.0
  Mn  Mn10  1  0.377  0.251  0.377  1.0
  Mn  Mn11  1  0.881  0.260  0.881  1.0
  Mn  Mn12  1  0.119  0.260  0.881  1.0
  Mn  Mn13  1  0.623  0.251  0.377  1.0
  Mn  Mn14  1  0.500  0.748  0.256  1.0
  Mn  Mn15  1  0.000  0.742  0.762  1.0
  Mn  Mn16  1  0.119  0.740  0.119  1.0
  Mn  Mn17  1  0.623  0.749  0.623  1.0
  Mn  Mn18  1  0.377  0.749  0.623  1.0
  Mn  Mn19  1  0.881  0.740  0.119  1.0
  Si  Si20  1  0.500  0.250  0.103  1.0
  Si  Si21  1  0.000  0.239  0.597  1.0
  Si  Si22  1  0.200  0.238  0.200  1.0
  Si  Si23  1  0.700  0.249  0.700  1.0
  Si  Si24  1  0.300  0.249  0.700  1.0
  Si  Si25  1  0.800  0.238  0.200  1.0
  Si  Si26  1  0.500  0.750  0.897  1.0
  Si  Si27  1  0.000  0.761  0.403  1.0
  Si  Si28  1  0.300  0.751  0.300  1.0
  Si  Si29  1  0.800  0.762  0.800  1.0
  Si  Si30  1  0.200  0.762  0.800  1.0
  Si  Si31  1  0.700  0.751  0.300  1.0
  C  C32  1  0.000  0.500  0.000  1.0
[/CIF]
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