The material described by Nb3B3C crystallizes in the orthorhombic Cmcm space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent B(2), four equivalent B(3), and six equivalent B(1) atoms to form NbB12 cuboctahedra that share corners with two equivalent Nb(2)BC5 square pyramids, edges with eight equivalent Nb(1)B12 cuboctahedra, and faces with six equivalent Nb(1)B12 cuboctahedra. In the second Nb site, Nb(2) is bonded to one B(2) and five equivalent C(1) atoms to form distorted NbBC5 square pyramids that share corners with two equivalent Nb(1)B12 cuboctahedra, corners with four equivalent Nb(2)BC5 square pyramids, and edges with eight equivalent Nb(2)BC5 square pyramids. In the third Nb site, Nb(3) is bonded in a 7-coordinate geometry to two equivalent B(3), four equivalent B(2), and one C(1) atom. There are three inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to six equivalent Nb(1), one B(3), and two equivalent B(1) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to one Nb(2), two equivalent Nb(1), four equivalent Nb(3), and two equivalent B(3) atoms. In the third B site, B(3) is bonded in a 9-coordinate geometry to two equivalent Nb(3), four equivalent Nb(1), one B(1), and two equivalent B(2) atoms. C(1) is bonded to one Nb(3) and five equivalent Nb(2) atoms to form a mixture of corner and edge-sharing CNb6 octahedra. The corner-sharing octahedral tilt angles are 1°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb3B3C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.541
_cell_length_b   14.541
_cell_length_c   3.142
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   167.044
_symmetry_Int_Tables_number   1
_cell_volume   148.964
_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
  Nb  Nb0  1  0.547  0.453  0.250  1.0
  Nb  Nb1  1  0.453  0.547  0.750  1.0
  Nb  Nb2  1  0.213  0.787  0.250  1.0
  Nb  Nb3  1  0.787  0.213  0.750  1.0
  Nb  Nb4  1  0.638  0.362  0.750  1.0
  Nb  Nb5  1  0.362  0.638  0.250  1.0
  B  B6  1  0.985  0.015  0.250  1.0
  B  B7  1  0.015  0.985  0.750  1.0
  B  B8  1  0.112  0.888  0.250  1.0
  B  B9  1  0.888  0.112  0.750  1.0
  B  B10  1  0.921  0.079  0.250  1.0
  B  B11  1  0.079  0.921  0.750  1.0
  C  C12  1  0.288  0.712  0.250  1.0
  C  C13  1  0.712  0.288  0.750  1.0
[/CIF]
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The material described by Nb3B3C crystallizes in the orthorhombic Cmcm space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent B(2), four equivalent B(3), and six equivalent B(1) atoms to form NbB12 cuboctahedra that share corners with two equivalent Nb(2)BC5 square pyramids, edges with eight equivalent Nb(1)B12 cuboctahedra, and faces with six equivalent Nb(1)B12 cuboctahedra. In the second Nb site, Nb(2) is bonded to one B(2) and five equivalent C(1) atoms to form distorted NbBC5 square pyramids that share corners with two equivalent Nb(1)B12 cuboctahedra, corners with four equivalent Nb(2)BC5 square pyramids, and edges with eight equivalent Nb(2)BC5 square pyramids. In the third Nb site, Nb(3) is bonded in a 7-coordinate geometry to two equivalent B(3), four equivalent B(2), and one C(1) atom. There are three inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to six equivalent Nb(1), one B(3), and two equivalent B(1) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to one Nb(2), two equivalent Nb(1), four equivalent Nb(3), and two equivalent B(3) atoms. In the third B site, B(3) is bonded in a 9-coordinate geometry to two equivalent Nb(3), four equivalent Nb(1), one B(1), and two equivalent B(2) atoms. C(1) is bonded to one Nb(3) and five equivalent Nb(2) atoms to form a mixture of corner and edge-sharing CNb6 octahedra. The corner-sharing octahedral tilt angles are 1°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb3B3C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.541
_cell_length_b   14.541
_cell_length_c   3.142
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   167.044
_symmetry_Int_Tables_number   1
_cell_volume   148.964
_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
  Nb  Nb0  1  0.547  0.453  0.250  1.0
  Nb  Nb1  1  0.453  0.547  0.750  1.0
  Nb  Nb2  1  0.213  0.787  0.250  1.0
  Nb  Nb3  1  0.787  0.213  0.750  1.0
  Nb  Nb4  1  0.638  0.362  0.750  1.0
  Nb  Nb5  1  0.362  0.638  0.250  1.0
  B  B6  1  0.985  0.015  0.250  1.0
  B  B7  1  0.015  0.985  0.750  1.0
  B  B8  1  0.112  0.888  0.250  1.0
  B  B9  1  0.888  0.112  0.750  1.0
  B  B10  1  0.921  0.079  0.250  1.0
  B  B11  1  0.079  0.921  0.750  1.0
  C  C12  1  0.288  0.712  0.250  1.0
  C  C13  1  0.712  0.288  0.750  1.0
[/CIF]
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