The compound described by Zr2Al3C4 crystallizes in the hexagonal P6_3/mmc space group. Zr(1) is bonded to three equivalent C(1) and three equivalent C(2) atoms to form ZrC6 octahedra that share corners with three equivalent Zr(1)C6 octahedra, corners with three equivalent Al(1)C4 tetrahedra, edges with nine equivalent Zr(1)C6 octahedra, and edges with three equivalent Al(1)C4 tetrahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one C(3) and three equivalent C(1) atoms to form AlC4 tetrahedra that share corners with three equivalent Zr(1)C6 octahedra, corners with seven equivalent Al(1)C4 tetrahedra, and edges with three equivalent Zr(1)C6 octahedra. The corner-sharing octahedral tilt angles are 19°. In the second Al site, Al(2) is bonded in a trigonal planar geometry to three equivalent C(3) atoms. There are three inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to three equivalent Zr(1) and three equivalent Al(1) atoms. In the second C site, C(2) is bonded to six equivalent Zr(1) atoms to form edge-sharing CZr6 octahedra. In the third C site, C(3) is bonded to two equivalent Al(1) and three equivalent Al(2) atoms to form corner-sharing CAl5 trigonal bipyramids. is represented by the CIF file [CIF]
data_Zr2Al3C4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.346
_cell_length_b   3.346
_cell_length_c   22.225
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   215.443
_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
  Zr  Zr0  1  0.333  0.667  0.059  1.0
  Zr  Zr1  1  0.667  0.333  0.941  1.0
  Zr  Zr2  1  0.333  0.667  0.441  1.0
  Zr  Zr3  1  0.667  0.333  0.559  1.0
  Al  Al4  1  0.000  0.000  0.340  1.0
  Al  Al5  1  0.000  0.000  0.840  1.0
  Al  Al6  1  0.000  0.000  0.660  1.0
  Al  Al7  1  0.667  0.333  0.250  1.0
  Al  Al8  1  0.000  0.000  0.160  1.0
  Al  Al9  1  0.333  0.667  0.750  1.0
  C  C10  1  0.667  0.333  0.371  1.0
  C  C11  1  0.333  0.667  0.629  1.0
  C  C12  1  0.333  0.667  0.871  1.0
  C  C13  1  0.000  0.000  0.000  1.0
  C  C14  1  0.667  0.333  0.129  1.0
  C  C15  1  0.000  0.000  0.250  1.0
  C  C16  1  0.000  0.000  0.500  1.0
  C  C17  1  0.000  0.000  0.750  1.0
[/CIF]
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The compound described by Zr2Al3C4 crystallizes in the hexagonal P6_3/mmc space group. Zr(1) is bonded to three equivalent C(1) and three equivalent C(2) atoms to form ZrC6 octahedra that share corners with three equivalent Zr(1)C6 octahedra, corners with three equivalent Al(1)C4 tetrahedra, edges with nine equivalent Zr(1)C6 octahedra, and edges with three equivalent Al(1)C4 tetrahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one C(3) and three equivalent C(1) atoms to form AlC4 tetrahedra that share corners with three equivalent Zr(1)C6 octahedra, corners with seven equivalent Al(1)C4 tetrahedra, and edges with three equivalent Zr(1)C6 octahedra. The corner-sharing octahedral tilt angles are 19°. In the second Al site, Al(2) is bonded in a trigonal planar geometry to three equivalent C(3) atoms. There are three inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to three equivalent Zr(1) and three equivalent Al(1) atoms. In the second C site, C(2) is bonded to six equivalent Zr(1) atoms to form edge-sharing CZr6 octahedra. In the third C site, C(3) is bonded to two equivalent Al(1) and three equivalent Al(2) atoms to form corner-sharing CAl5 trigonal bipyramids. is represented by the CIF file [CIF]
data_Zr2Al3C4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.346
_cell_length_b   3.346
_cell_length_c   22.225
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   215.443
_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
  Zr  Zr0  1  0.333  0.667  0.059  1.0
  Zr  Zr1  1  0.667  0.333  0.941  1.0
  Zr  Zr2  1  0.333  0.667  0.441  1.0
  Zr  Zr3  1  0.667  0.333  0.559  1.0
  Al  Al4  1  0.000  0.000  0.340  1.0
  Al  Al5  1  0.000  0.000  0.840  1.0
  Al  Al6  1  0.000  0.000  0.660  1.0
  Al  Al7  1  0.667  0.333  0.250  1.0
  Al  Al8  1  0.000  0.000  0.160  1.0
  Al  Al9  1  0.333  0.667  0.750  1.0
  C  C10  1  0.667  0.333  0.371  1.0
  C  C11  1  0.333  0.667  0.629  1.0
  C  C12  1  0.333  0.667  0.871  1.0
  C  C13  1  0.000  0.000  0.000  1.0
  C  C14  1  0.667  0.333  0.129  1.0
  C  C15  1  0.000  0.000  0.250  1.0
  C  C16  1  0.000  0.000  0.500  1.0
  C  C17  1  0.000  0.000  0.750  1.0
[/CIF]
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