The crystal structure described by EuYSi4N7 crystallizes in the hexagonal P6_3mc space group. Eu(1) is bonded to six equivalent N(2) and six equivalent N(3) atoms to form distorted EuN12 cuboctahedra that share corners with twelve equivalent Eu(1)N12 cuboctahedra, edges with three equivalent Si(2)N4 tetrahedra, edges with nine equivalent Si(1)N4 tetrahedra, and faces with four equivalent Y(1)N6 octahedra. Y(1) is bonded to three equivalent N(2) and three equivalent N(3) atoms to form YN6 octahedra that share corners with three equivalent Si(2)N4 tetrahedra, corners with nine equivalent Si(1)N4 tetrahedra, and faces with four equivalent Eu(1)N12 cuboctahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one N(2), and two equivalent N(3) atoms to form SiN4 tetrahedra that share corners with three equivalent Y(1)N6 octahedra, corners with two equivalent Si(2)N4 tetrahedra, corners with four equivalent Si(1)N4 tetrahedra, and edges with three equivalent Eu(1)N12 cuboctahedra. The corner-sharing octahedral tilt angles range from 57-62°. In the second Si site, Si(2) is bonded to one N(1) and three equivalent N(2) atoms to form SiN4 tetrahedra that share corners with three equivalent Y(1)N6 octahedra, corners with six equivalent Si(1)N4 tetrahedra, and edges with three equivalent Eu(1)N12 cuboctahedra. The corner-sharing octahedral tilt angles are 56°. There are three inequivalent N sites. In the first N site, N(1) is bonded in a tetrahedral geometry to one Si(2) and three equivalent Si(1) atoms. In the second N site, N(2) is bonded in a distorted trigonal planar geometry to two equivalent Eu(1), one Y(1), one Si(1), and one Si(2) atom. In the third N site, N(3) is bonded in a 3-coordinate geometry to two equivalent Eu(1), one Y(1), and two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_EuYSi4N7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.046
_cell_length_b   6.046
_cell_length_c   9.884
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   312.940
_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
  Eu  Eu0  1  0.333  0.667  0.087  1.0
  Eu  Eu1  1  0.667  0.333  0.587  1.0
  Y  Y2  1  0.333  0.667  0.452  1.0
  Y  Y3  1  0.667  0.333  0.952  1.0
  Si  Si4  1  0.174  0.347  0.761  1.0
  Si  Si5  1  0.826  0.174  0.261  1.0
  Si  Si6  1  0.347  0.174  0.261  1.0
  Si  Si7  1  0.653  0.826  0.761  1.0
  Si  Si8  1  0.174  0.826  0.761  1.0
  Si  Si9  1  0.826  0.653  0.261  1.0
  Si  Si10  1  0.000  0.000  0.028  1.0
  Si  Si11  1  0.000  0.000  0.528  1.0
  N  N12  1  0.000  0.000  0.838  1.0
  N  N13  1  0.000  0.000  0.338  1.0
  N  N14  1  0.847  0.694  0.089  1.0
  N  N15  1  0.153  0.847  0.589  1.0
  N  N16  1  0.694  0.847  0.589  1.0
  N  N17  1  0.306  0.153  0.089  1.0
  N  N18  1  0.847  0.153  0.089  1.0
  N  N19  1  0.153  0.306  0.589  1.0
  N  N20  1  0.489  0.511  0.812  1.0
  N  N21  1  0.978  0.489  0.312  1.0
  N  N22  1  0.511  0.022  0.312  1.0
  N  N23  1  0.489  0.978  0.812  1.0
  N  N24  1  0.511  0.489  0.312  1.0
  N  N25  1  0.022  0.511  0.812  1.0
[/CIF]
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The crystal structure described by EuYSi4N7 crystallizes in the hexagonal P6_3mc space group. Eu(1) is bonded to six equivalent N(2) and six equivalent N(3) atoms to form distorted EuN12 cuboctahedra that share corners with twelve equivalent Eu(1)N12 cuboctahedra, edges with three equivalent Si(2)N4 tetrahedra, edges with nine equivalent Si(1)N4 tetrahedra, and faces with four equivalent Y(1)N6 octahedra. Y(1) is bonded to three equivalent N(2) and three equivalent N(3) atoms to form YN6 octahedra that share corners with three equivalent Si(2)N4 tetrahedra, corners with nine equivalent Si(1)N4 tetrahedra, and faces with four equivalent Eu(1)N12 cuboctahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one N(2), and two equivalent N(3) atoms to form SiN4 tetrahedra that share corners with three equivalent Y(1)N6 octahedra, corners with two equivalent Si(2)N4 tetrahedra, corners with four equivalent Si(1)N4 tetrahedra, and edges with three equivalent Eu(1)N12 cuboctahedra. The corner-sharing octahedral tilt angles range from 57-62°. In the second Si site, Si(2) is bonded to one N(1) and three equivalent N(2) atoms to form SiN4 tetrahedra that share corners with three equivalent Y(1)N6 octahedra, corners with six equivalent Si(1)N4 tetrahedra, and edges with three equivalent Eu(1)N12 cuboctahedra. The corner-sharing octahedral tilt angles are 56°. There are three inequivalent N sites. In the first N site, N(1) is bonded in a tetrahedral geometry to one Si(2) and three equivalent Si(1) atoms. In the second N site, N(2) is bonded in a distorted trigonal planar geometry to two equivalent Eu(1), one Y(1), one Si(1), and one Si(2) atom. In the third N site, N(3) is bonded in a 3-coordinate geometry to two equivalent Eu(1), one Y(1), and two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_EuYSi4N7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.046
_cell_length_b   6.046
_cell_length_c   9.884
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   312.940
_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
  Eu  Eu0  1  0.333  0.667  0.087  1.0
  Eu  Eu1  1  0.667  0.333  0.587  1.0
  Y  Y2  1  0.333  0.667  0.452  1.0
  Y  Y3  1  0.667  0.333  0.952  1.0
  Si  Si4  1  0.174  0.347  0.761  1.0
  Si  Si5  1  0.826  0.174  0.261  1.0
  Si  Si6  1  0.347  0.174  0.261  1.0
  Si  Si7  1  0.653  0.826  0.761  1.0
  Si  Si8  1  0.174  0.826  0.761  1.0
  Si  Si9  1  0.826  0.653  0.261  1.0
  Si  Si10  1  0.000  0.000  0.028  1.0
  Si  Si11  1  0.000  0.000  0.528  1.0
  N  N12  1  0.000  0.000  0.838  1.0
  N  N13  1  0.000  0.000  0.338  1.0
  N  N14  1  0.847  0.694  0.089  1.0
  N  N15  1  0.153  0.847  0.589  1.0
  N  N16  1  0.694  0.847  0.589  1.0
  N  N17  1  0.306  0.153  0.089  1.0
  N  N18  1  0.847  0.153  0.089  1.0
  N  N19  1  0.153  0.306  0.589  1.0
  N  N20  1  0.489  0.511  0.812  1.0
  N  N21  1  0.978  0.489  0.312  1.0
  N  N22  1  0.511  0.022  0.312  1.0
  N  N23  1  0.489  0.978  0.812  1.0
  N  N24  1  0.511  0.489  0.312  1.0
  N  N25  1  0.022  0.511  0.812  1.0
[/CIF]
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