The crystal structure described by Sm2Mn17C2 crystallizes in the monoclinic C2/m space group. Sm(1) is bonded in a distorted bent 120 degrees geometry to one Mn(1), one Mn(6), two equivalent Mn(2), two equivalent Mn(7), three equivalent Mn(5), and two equivalent C(1) atoms. There are seven inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 14-coordinate geometry to one Sm(1), one Mn(1), one Mn(5), one Mn(6), two equivalent Mn(2), two equivalent Mn(4), two equivalent Mn(7), and four equivalent Mn(3) atoms. In the second Mn site, Mn(2) is bonded to two equivalent Sm(1), two equivalent Mn(1), two equivalent Mn(3), two equivalent Mn(4), two equivalent Mn(5), and two equivalent Mn(7) atoms to form distorted MnSm2Mn10 cuboctahedra that share corners with two equivalent Mn(2)Sm2Mn10 cuboctahedra, corners with two equivalent Mn(7)Sm2Mn10 cuboctahedra, corners with four equivalent C(1)Sm2Mn4 octahedra,  an edgeedge with one Mn(2)Sm2Mn10 cuboctahedra, edges with two equivalent Mn(7)Sm2Mn10 cuboctahedra, edges with two equivalent C(1)Sm2Mn4 octahedra,  a faceface with one Mn(2)Sm2Mn10 cuboctahedra, and faces with two equivalent Mn(7)Sm2Mn10 cuboctahedra. The corner-sharing octahedral tilt angles range from 22-28°. In the third Mn site, Mn(3) is bonded in a single-bond geometry to one Mn(2), one Mn(5), one Mn(6), one Mn(7), two equivalent Mn(1), and one C(1) atom. In the fourth Mn site, Mn(4) is bonded in a single-bond geometry to one Mn(1), one Mn(2), one Mn(5), one Mn(6), one Mn(7), and one C(1) atom. In the fifth Mn site, Mn(5) is bonded in a 12-coordinate geometry to three equivalent Sm(1), one Mn(1), two equivalent Mn(2), two equivalent Mn(3), two equivalent Mn(4), and two equivalent Mn(7) atoms. In the sixth Mn site, Mn(6) is bonded in a 12-coordinate geometry to two equivalent Sm(1), two equivalent Mn(1), four equivalent Mn(3), and four equivalent Mn(4) atoms. In the seventh Mn site, Mn(7) is bonded to two equivalent Sm(1), two equivalent Mn(1), two equivalent Mn(2), two equivalent Mn(3), two equivalent Mn(4), and two equivalent Mn(5) atoms to form distorted MnSm2Mn10 cuboctahedra that share corners with two equivalent Mn(2)Sm2Mn10 cuboctahedra, corners with two equivalent Mn(7)Sm2Mn10 cuboctahedra, corners with two equivalent C(1)Sm2Mn4 octahedra, edges with two equivalent Mn(2)Sm2Mn10 cuboctahedra, faces with two equivalent Mn(2)Sm2Mn10 cuboctahedra, faces with two equivalent Mn(7)Sm2Mn10 cuboctahedra, and faces with two equivalent C(1)Sm2Mn4 octahedra. The corner-sharing octahedral tilt angles are 48°. C(1) is bonded to two equivalent Sm(1), two equivalent Mn(3), and two equivalent Mn(4) atoms to form CSm2Mn4 octahedra that share corners with two equivalent Mn(7)Sm2Mn10 cuboctahedra, corners with four equivalent Mn(2)Sm2Mn10 cuboctahedra, corners with two equivalent C(1)Sm2Mn4 octahedra, edges with two equivalent Mn(2)Sm2Mn10 cuboctahedra, and faces with two equivalent Mn(7)Sm2Mn10 cuboctahedra. The corner-sharing octahedral tilt angles are 63°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm2Mn17C2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.457
_cell_length_b   6.457
_cell_length_c   6.467
_cell_angle_alpha   83.736
_cell_angle_beta   83.736
_cell_angle_gamma   83.997
_symmetry_Int_Tables_number   1
_cell_volume   265.257
_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
  Sm  Sm0  1  0.644  0.644  0.655  1.0
  Sm  Sm1  1  0.356  0.356  0.345  1.0
  Mn  Mn2  1  0.905  0.905  0.905  1.0
  Mn  Mn3  1  0.095  0.095  0.095  1.0
  Mn  Mn4  1  0.271  0.729  0.000  1.0
  Mn  Mn5  1  0.719  0.993  0.280  1.0
  Mn  Mn6  1  0.007  0.281  0.720  1.0
  Mn  Mn7  1  0.281  0.007  0.720  1.0
  Mn  Mn8  1  0.993  0.719  0.280  1.0
  Mn  Mn9  1  0.729  0.271  0.000  1.0
  Mn  Mn10  1  0.867  0.335  0.338  1.0
  Mn  Mn11  1  0.346  0.346  0.871  1.0
  Mn  Mn12  1  0.335  0.867  0.338  1.0
  Mn  Mn13  1  0.133  0.665  0.662  1.0
  Mn  Mn14  1  0.654  0.654  0.129  1.0
  Mn  Mn15  1  0.665  0.133  0.662  1.0
  Mn  Mn16  1  0.000  0.000  0.500  1.0
  Mn  Mn17  1  0.000  0.500  0.000  1.0
  Mn  Mn18  1  0.500  0.000  0.000  1.0
  C  C19  1  0.500  0.000  0.500  1.0
  C  C20  1  0.000  0.500  0.500  1.0
[/CIF]
.
The crystal structure described by Sm2Mn17C2 crystallizes in the monoclinic C2/m space group. Sm(1) is bonded in a distorted bent 120 degrees geometry to one Mn(1), one Mn(6), two equivalent Mn(2), two equivalent Mn(7), three equivalent Mn(5), and two equivalent C(1) atoms. There are seven inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 14-coordinate geometry to one Sm(1), one Mn(1), one Mn(5), one Mn(6), two equivalent Mn(2), two equivalent Mn(4), two equivalent Mn(7), and four equivalent Mn(3) atoms. In the second Mn site, Mn(2) is bonded to two equivalent Sm(1), two equivalent Mn(1), two equivalent Mn(3), two equivalent Mn(4), two equivalent Mn(5), and two equivalent Mn(7) atoms to form distorted MnSm2Mn10 cuboctahedra that share corners with two equivalent Mn(2)Sm2Mn10 cuboctahedra, corners with two equivalent Mn(7)Sm2Mn10 cuboctahedra, corners with four equivalent C(1)Sm2Mn4 octahedra,  an edgeedge with one Mn(2)Sm2Mn10 cuboctahedra, edges with two equivalent Mn(7)Sm2Mn10 cuboctahedra, edges with two equivalent C(1)Sm2Mn4 octahedra,  a faceface with one Mn(2)Sm2Mn10 cuboctahedra, and faces with two equivalent Mn(7)Sm2Mn10 cuboctahedra. The corner-sharing octahedral tilt angles range from 22-28°. In the third Mn site, Mn(3) is bonded in a single-bond geometry to one Mn(2), one Mn(5), one Mn(6), one Mn(7), two equivalent Mn(1), and one C(1) atom. In the fourth Mn site, Mn(4) is bonded in a single-bond geometry to one Mn(1), one Mn(2), one Mn(5), one Mn(6), one Mn(7), and one C(1) atom. In the fifth Mn site, Mn(5) is bonded in a 12-coordinate geometry to three equivalent Sm(1), one Mn(1), two equivalent Mn(2), two equivalent Mn(3), two equivalent Mn(4), and two equivalent Mn(7) atoms. In the sixth Mn site, Mn(6) is bonded in a 12-coordinate geometry to two equivalent Sm(1), two equivalent Mn(1), four equivalent Mn(3), and four equivalent Mn(4) atoms. In the seventh Mn site, Mn(7) is bonded to two equivalent Sm(1), two equivalent Mn(1), two equivalent Mn(2), two equivalent Mn(3), two equivalent Mn(4), and two equivalent Mn(5) atoms to form distorted MnSm2Mn10 cuboctahedra that share corners with two equivalent Mn(2)Sm2Mn10 cuboctahedra, corners with two equivalent Mn(7)Sm2Mn10 cuboctahedra, corners with two equivalent C(1)Sm2Mn4 octahedra, edges with two equivalent Mn(2)Sm2Mn10 cuboctahedra, faces with two equivalent Mn(2)Sm2Mn10 cuboctahedra, faces with two equivalent Mn(7)Sm2Mn10 cuboctahedra, and faces with two equivalent C(1)Sm2Mn4 octahedra. The corner-sharing octahedral tilt angles are 48°. C(1) is bonded to two equivalent Sm(1), two equivalent Mn(3), and two equivalent Mn(4) atoms to form CSm2Mn4 octahedra that share corners with two equivalent Mn(7)Sm2Mn10 cuboctahedra, corners with four equivalent Mn(2)Sm2Mn10 cuboctahedra, corners with two equivalent C(1)Sm2Mn4 octahedra, edges with two equivalent Mn(2)Sm2Mn10 cuboctahedra, and faces with two equivalent Mn(7)Sm2Mn10 cuboctahedra. The corner-sharing octahedral tilt angles are 63°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm2Mn17C2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.457
_cell_length_b   6.457
_cell_length_c   6.467
_cell_angle_alpha   83.736
_cell_angle_beta   83.736
_cell_angle_gamma   83.997
_symmetry_Int_Tables_number   1
_cell_volume   265.257
_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
  Sm  Sm0  1  0.644  0.644  0.655  1.0
  Sm  Sm1  1  0.356  0.356  0.345  1.0
  Mn  Mn2  1  0.905  0.905  0.905  1.0
  Mn  Mn3  1  0.095  0.095  0.095  1.0
  Mn  Mn4  1  0.271  0.729  0.000  1.0
  Mn  Mn5  1  0.719  0.993  0.280  1.0
  Mn  Mn6  1  0.007  0.281  0.720  1.0
  Mn  Mn7  1  0.281  0.007  0.720  1.0
  Mn  Mn8  1  0.993  0.719  0.280  1.0
  Mn  Mn9  1  0.729  0.271  0.000  1.0
  Mn  Mn10  1  0.867  0.335  0.338  1.0
  Mn  Mn11  1  0.346  0.346  0.871  1.0
  Mn  Mn12  1  0.335  0.867  0.338  1.0
  Mn  Mn13  1  0.133  0.665  0.662  1.0
  Mn  Mn14  1  0.654  0.654  0.129  1.0
  Mn  Mn15  1  0.665  0.133  0.662  1.0
  Mn  Mn16  1  0.000  0.000  0.500  1.0
  Mn  Mn17  1  0.000  0.500  0.000  1.0
  Mn  Mn18  1  0.500  0.000  0.000  1.0
  C  C19  1  0.500  0.000  0.500  1.0
  C  C20  1  0.000  0.500  0.500  1.0
[/CIF]
.