The crystal structure described by Be2Y2Fe(SiO5)2 is Esseneite-derived structured and crystallizes in the monoclinic P2_1/c space group. Be(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form BeO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with three equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 63°. Y(1) is bonded in a 8-coordinate geometry to one O(1), one O(3), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent Be(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Be(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with three equivalent Be(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 65-69°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Be(1), one Y(1), one Fe(1), and one Si(1) atom. In the second O site, O(2) is bonded to one Be(1), two equivalent Y(1), and one Fe(1) atom to form distorted corner-sharing OY2BeFe tetrahedra. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Be(1), one Y(1), one Fe(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Y(1) and one Si(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Be(1), two equivalent Y(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_Y2Be2Fe(SiO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.571
_cell_length_b   4.793
_cell_length_c   10.041
_cell_angle_alpha   89.451
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   364.348
_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
  Y  Y0  1  0.606  0.001  0.829  1.0
  Y  Y1  1  0.106  0.999  0.671  1.0
  Y  Y2  1  0.394  0.999  0.171  1.0
  Y  Y3  1  0.894  0.001  0.329  1.0
  Be  Be4  1  0.913  0.534  0.835  1.0
  Be  Be5  1  0.413  0.466  0.665  1.0
  Be  Be6  1  0.087  0.466  0.165  1.0
  Be  Be7  1  0.587  0.534  0.335  1.0
  Fe  Fe8  1  0.000  0.000  0.000  1.0
  Fe  Fe9  1  0.500  0.000  0.500  1.0
  Si  Si10  1  0.780  0.481  0.578  1.0
  Si  Si11  1  0.280  0.519  0.922  1.0
  Si  Si12  1  0.220  0.519  0.422  1.0
  Si  Si13  1  0.720  0.481  0.078  1.0
  O  O14  1  0.607  0.314  0.642  1.0
  O  O15  1  0.107  0.686  0.858  1.0
  O  O16  1  0.393  0.686  0.358  1.0
  O  O17  1  0.893  0.314  0.142  1.0
  O  O18  1  0.413  0.798  0.668  1.0
  O  O19  1  0.913  0.202  0.832  1.0
  O  O20  1  0.587  0.202  0.332  1.0
  O  O21  1  0.213  0.324  0.049  1.0
  O  O22  1  0.586  0.238  0.029  1.0
  O  O23  1  0.086  0.762  0.471  1.0
  O  O24  1  0.848  0.691  0.696  1.0
  O  O25  1  0.914  0.238  0.529  1.0
  O  O26  1  0.713  0.676  0.451  1.0
  O  O27  1  0.414  0.762  0.971  1.0
  O  O28  1  0.287  0.324  0.549  1.0
  O  O29  1  0.787  0.676  0.951  1.0
  O  O30  1  0.652  0.691  0.196  1.0
  O  O31  1  0.152  0.309  0.304  1.0
  O  O32  1  0.348  0.309  0.804  1.0
  O  O33  1  0.087  0.798  0.168  1.0
[/CIF]
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The crystal structure described by Be2Y2Fe(SiO5)2 is Esseneite-derived structured and crystallizes in the monoclinic P2_1/c space group. Be(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form BeO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with three equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 63°. Y(1) is bonded in a 8-coordinate geometry to one O(1), one O(3), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent Be(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Be(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with three equivalent Be(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 65-69°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Be(1), one Y(1), one Fe(1), and one Si(1) atom. In the second O site, O(2) is bonded to one Be(1), two equivalent Y(1), and one Fe(1) atom to form distorted corner-sharing OY2BeFe tetrahedra. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Be(1), one Y(1), one Fe(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Y(1) and one Si(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Be(1), two equivalent Y(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_Y2Be2Fe(SiO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.571
_cell_length_b   4.793
_cell_length_c   10.041
_cell_angle_alpha   89.451
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   364.348
_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
  Y  Y0  1  0.606  0.001  0.829  1.0
  Y  Y1  1  0.106  0.999  0.671  1.0
  Y  Y2  1  0.394  0.999  0.171  1.0
  Y  Y3  1  0.894  0.001  0.329  1.0
  Be  Be4  1  0.913  0.534  0.835  1.0
  Be  Be5  1  0.413  0.466  0.665  1.0
  Be  Be6  1  0.087  0.466  0.165  1.0
  Be  Be7  1  0.587  0.534  0.335  1.0
  Fe  Fe8  1  0.000  0.000  0.000  1.0
  Fe  Fe9  1  0.500  0.000  0.500  1.0
  Si  Si10  1  0.780  0.481  0.578  1.0
  Si  Si11  1  0.280  0.519  0.922  1.0
  Si  Si12  1  0.220  0.519  0.422  1.0
  Si  Si13  1  0.720  0.481  0.078  1.0
  O  O14  1  0.607  0.314  0.642  1.0
  O  O15  1  0.107  0.686  0.858  1.0
  O  O16  1  0.393  0.686  0.358  1.0
  O  O17  1  0.893  0.314  0.142  1.0
  O  O18  1  0.413  0.798  0.668  1.0
  O  O19  1  0.913  0.202  0.832  1.0
  O  O20  1  0.587  0.202  0.332  1.0
  O  O21  1  0.213  0.324  0.049  1.0
  O  O22  1  0.586  0.238  0.029  1.0
  O  O23  1  0.086  0.762  0.471  1.0
  O  O24  1  0.848  0.691  0.696  1.0
  O  O25  1  0.914  0.238  0.529  1.0
  O  O26  1  0.713  0.676  0.451  1.0
  O  O27  1  0.414  0.762  0.971  1.0
  O  O28  1  0.287  0.324  0.549  1.0
  O  O29  1  0.787  0.676  0.951  1.0
  O  O30  1  0.652  0.691  0.196  1.0
  O  O31  1  0.152  0.309  0.304  1.0
  O  O32  1  0.348  0.309  0.804  1.0
  O  O33  1  0.087  0.798  0.168  1.0
[/CIF]
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