The material structure described by LuFe7Al3Si2 crystallizes in the monoclinic Cm space group. Lu(1) is bonded in a 20-coordinate geometry to one Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), four equivalent Fe(6), one Al(1), one Al(2), one Al(3), and four equivalent Si(1) atoms. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Lu(1), one Fe(2), one Fe(3), two equivalent Fe(4), two equivalent Fe(6), one Al(3), two equivalent Al(1), two equivalent Al(2), and two equivalent Si(1) atoms. In the second Fe site, Fe(2) is bonded in a 12-coordinate geometry to two equivalent Lu(1), one Fe(1), one Fe(4), one Fe(5), two equivalent Fe(6), one Al(3), two equivalent Al(2), and two equivalent Si(1) atoms. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Lu(1), one Fe(1), one Fe(4), one Fe(5), two equivalent Fe(6), one Al(3), two equivalent Al(1), and two equivalent Si(1) atoms. In the fourth Fe site, Fe(4) is bonded in a 12-coordinate geometry to two equivalent Lu(1), one Fe(2), one Fe(3), two equivalent Fe(1), two equivalent Fe(6), one Al(1), one Al(2), and two equivalent Si(1) atoms. In the fifth Fe site, Fe(5) is bonded in a 12-coordinate geometry to two equivalent Lu(1), one Fe(2), one Fe(3), two equivalent Fe(6), one Al(1), one Al(2), two equivalent Al(3), and two equivalent Si(1) atoms. In the sixth Fe site, Fe(6) is bonded to two equivalent Lu(1), one Fe(1), one Fe(2), one Fe(3), one Fe(4), one Fe(5), two equivalent Fe(6), one Al(1), one Al(2), and one Al(3) atom to form distorted FeLu2Al3Fe7 cuboctahedra that share corners with four equivalent Si(1)Lu2Al3Fe5Si2 cuboctahedra, corners with six equivalent Fe(6)Lu2Al3Fe7 cuboctahedra, edges with four equivalent Si(1)Lu2Al3Fe5Si2 cuboctahedra, faces with two equivalent Fe(6)Lu2Al3Fe7 cuboctahedra, and faces with four equivalent Si(1)Lu2Al3Fe5Si2 cuboctahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded in a 14-coordinate geometry to one Lu(1), one Fe(4), one Fe(5), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(6), one Al(2), two equivalent Al(3), and two equivalent Si(1) atoms. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to one Lu(1), one Fe(4), one Fe(5), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(6), one Al(1), and two equivalent Si(1) atoms. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Lu(1), one Fe(1), one Fe(2), one Fe(3), two equivalent Fe(5), two equivalent Fe(6), two equivalent Al(1), and two equivalent Si(1) atoms. Si(1) is bonded to two equivalent Lu(1), one Fe(1), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Al(1), one Al(2), one Al(3), and two equivalent Si(1) atoms to form distorted SiLu2Al3Fe5Si2 cuboctahedra that share corners with four equivalent Fe(6)Lu2Al3Fe7 cuboctahedra, corners with six equivalent Si(1)Lu2Al3Fe5Si2 cuboctahedra, edges with four equivalent Fe(6)Lu2Al3Fe7 cuboctahedra, faces with two equivalent Si(1)Lu2Al3Fe5Si2 cuboctahedra, and faces with four equivalent Fe(6)Lu2Al3Fe7 cuboctahedra. is represented by the CIF file [CIF]
data_LuAl3Fe7Si2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.824
_cell_length_b   6.397
_cell_length_c   6.427
_cell_angle_alpha   98.285
_cell_angle_beta   112.041
_cell_angle_gamma   67.847
_symmetry_Int_Tables_number   1
_cell_volume   170.266
_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
  Lu  Lu0  1  0.999  0.996  0.995  1.0
  Al  Al1  1  0.649  0.342  0.639  1.0
  Al  Al2  1  0.351  0.660  0.362  1.0
  Al  Al3  1  0.009  0.348  0.367  1.0
  Fe  Fe4  1  0.003  0.648  0.653  1.0
  Fe  Fe5  1  0.726  0.768  0.220  1.0
  Fe  Fe6  1  0.280  0.222  0.782  1.0
  Fe  Fe7  1  0.503  0.778  0.784  1.0
  Fe  Fe8  1  0.492  0.235  0.218  1.0
  Fe  Fe9  1  0.502  0.999  0.497  1.0
  Fe  Fe10  1  0.996  0.999  0.497  1.0
  Si  Si11  1  0.492  0.503  0.993  1.0
  Si  Si12  1  0.998  0.503  0.993  1.0
[/CIF]
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The material structure described by LuFe7Al3Si2 crystallizes in the monoclinic Cm space group. Lu(1) is bonded in a 20-coordinate geometry to one Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), four equivalent Fe(6), one Al(1), one Al(2), one Al(3), and four equivalent Si(1) atoms. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Lu(1), one Fe(2), one Fe(3), two equivalent Fe(4), two equivalent Fe(6), one Al(3), two equivalent Al(1), two equivalent Al(2), and two equivalent Si(1) atoms. In the second Fe site, Fe(2) is bonded in a 12-coordinate geometry to two equivalent Lu(1), one Fe(1), one Fe(4), one Fe(5), two equivalent Fe(6), one Al(3), two equivalent Al(2), and two equivalent Si(1) atoms. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Lu(1), one Fe(1), one Fe(4), one Fe(5), two equivalent Fe(6), one Al(3), two equivalent Al(1), and two equivalent Si(1) atoms. In the fourth Fe site, Fe(4) is bonded in a 12-coordinate geometry to two equivalent Lu(1), one Fe(2), one Fe(3), two equivalent Fe(1), two equivalent Fe(6), one Al(1), one Al(2), and two equivalent Si(1) atoms. In the fifth Fe site, Fe(5) is bonded in a 12-coordinate geometry to two equivalent Lu(1), one Fe(2), one Fe(3), two equivalent Fe(6), one Al(1), one Al(2), two equivalent Al(3), and two equivalent Si(1) atoms. In the sixth Fe site, Fe(6) is bonded to two equivalent Lu(1), one Fe(1), one Fe(2), one Fe(3), one Fe(4), one Fe(5), two equivalent Fe(6), one Al(1), one Al(2), and one Al(3) atom to form distorted FeLu2Al3Fe7 cuboctahedra that share corners with four equivalent Si(1)Lu2Al3Fe5Si2 cuboctahedra, corners with six equivalent Fe(6)Lu2Al3Fe7 cuboctahedra, edges with four equivalent Si(1)Lu2Al3Fe5Si2 cuboctahedra, faces with two equivalent Fe(6)Lu2Al3Fe7 cuboctahedra, and faces with four equivalent Si(1)Lu2Al3Fe5Si2 cuboctahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded in a 14-coordinate geometry to one Lu(1), one Fe(4), one Fe(5), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(6), one Al(2), two equivalent Al(3), and two equivalent Si(1) atoms. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to one Lu(1), one Fe(4), one Fe(5), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(6), one Al(1), and two equivalent Si(1) atoms. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Lu(1), one Fe(1), one Fe(2), one Fe(3), two equivalent Fe(5), two equivalent Fe(6), two equivalent Al(1), and two equivalent Si(1) atoms. Si(1) is bonded to two equivalent Lu(1), one Fe(1), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Al(1), one Al(2), one Al(3), and two equivalent Si(1) atoms to form distorted SiLu2Al3Fe5Si2 cuboctahedra that share corners with four equivalent Fe(6)Lu2Al3Fe7 cuboctahedra, corners with six equivalent Si(1)Lu2Al3Fe5Si2 cuboctahedra, edges with four equivalent Fe(6)Lu2Al3Fe7 cuboctahedra, faces with two equivalent Si(1)Lu2Al3Fe5Si2 cuboctahedra, and faces with four equivalent Fe(6)Lu2Al3Fe7 cuboctahedra. is represented by the CIF file [CIF]
data_LuAl3Fe7Si2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.824
_cell_length_b   6.397
_cell_length_c   6.427
_cell_angle_alpha   98.285
_cell_angle_beta   112.041
_cell_angle_gamma   67.847
_symmetry_Int_Tables_number   1
_cell_volume   170.266
_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
  Lu  Lu0  1  0.999  0.996  0.995  1.0
  Al  Al1  1  0.649  0.342  0.639  1.0
  Al  Al2  1  0.351  0.660  0.362  1.0
  Al  Al3  1  0.009  0.348  0.367  1.0
  Fe  Fe4  1  0.003  0.648  0.653  1.0
  Fe  Fe5  1  0.726  0.768  0.220  1.0
  Fe  Fe6  1  0.280  0.222  0.782  1.0
  Fe  Fe7  1  0.503  0.778  0.784  1.0
  Fe  Fe8  1  0.492  0.235  0.218  1.0
  Fe  Fe9  1  0.502  0.999  0.497  1.0
  Fe  Fe10  1  0.996  0.999  0.497  1.0
  Si  Si11  1  0.492  0.503  0.993  1.0
  Si  Si12  1  0.998  0.503  0.993  1.0
[/CIF]
.