The structure described by Cr3AlB4 crystallizes in the orthorhombic Pmmm space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a 6-coordinate geometry to two equivalent B(1) and four equivalent B(2) atoms. In the second Cr site, Cr(2) is bonded to four equivalent B(2) and eight equivalent B(1) atoms to form a mixture of edge and face-sharing CrB12 cuboctahedra. Al(1) is bonded in a distorted linear geometry to two equivalent B(2) atoms. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to two equivalent Cr(1), four equivalent Cr(2), one B(1), and two equivalent B(2) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Cr(2), four equivalent Cr(1), one Al(1), and two equivalent B(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_AlCr3B4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.921
_cell_length_b   2.918
_cell_length_c   8.058
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   68.692
_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
  Al  Al0  1  0.500  0.500  0.500  1.0
  Cr  Cr1  1  0.000  0.000  0.702  1.0
  Cr  Cr2  1  0.000  0.000  0.298  1.0
  Cr  Cr3  1  0.000  0.500  0.000  1.0
  B  B4  1  0.500  0.000  0.108  1.0
  B  B5  1  0.500  0.500  0.224  1.0
  B  B6  1  0.500  0.000  0.892  1.0
  B  B7  1  0.500  0.500  0.776  1.0
[/CIF]
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The structure described by Cr3AlB4 crystallizes in the orthorhombic Pmmm space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a 6-coordinate geometry to two equivalent B(1) and four equivalent B(2) atoms. In the second Cr site, Cr(2) is bonded to four equivalent B(2) and eight equivalent B(1) atoms to form a mixture of edge and face-sharing CrB12 cuboctahedra. Al(1) is bonded in a distorted linear geometry to two equivalent B(2) atoms. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to two equivalent Cr(1), four equivalent Cr(2), one B(1), and two equivalent B(2) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Cr(2), four equivalent Cr(1), one Al(1), and two equivalent B(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_AlCr3B4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.921
_cell_length_b   2.918
_cell_length_c   8.058
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   68.692
_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
  Al  Al0  1  0.500  0.500  0.500  1.0
  Cr  Cr1  1  0.000  0.000  0.702  1.0
  Cr  Cr2  1  0.000  0.000  0.298  1.0
  Cr  Cr3  1  0.000  0.500  0.000  1.0
  B  B4  1  0.500  0.000  0.108  1.0
  B  B5  1  0.500  0.500  0.224  1.0
  B  B6  1  0.500  0.000  0.892  1.0
  B  B7  1  0.500  0.500  0.776  1.0
[/CIF]
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