data_Sr2YNb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.52
_cell_length_b   3.52
_cell_length_c   11.22
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Sr2YNb
_chemical_formula_sum   'Sr2 Y1 Nb1'
_cell_volume   139.21
_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
  Sr  Sr1  1  0.0  0.0  0.63  1.0
  Sr  Sr2  1  0.76  0.76  0.99  1.0
  Y  Y3  1  0.0  0.0  0.25  1.0
  Nb  Nb0  1  0.76  0.76  0.19  1.0

data_Sr2YNb
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.98
_cell_length_b   4.98
_cell_length_c   11.22
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Sr2YNb
_chemical_formula_sum   'Sr4 Y2 Nb2'
_cell_volume   278.43
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Sr  Sr0  2  0.0  0.0  0.63  1.0
  Sr  Sr1  2  0.26  0.5  0.99  1.0
  Y  Y2  2  0.0  0.0  0.25  1.0
  Nb  Nb3  2  0.26  0.5  0.19  1.0

Sr Sr Y Nb
Sr Sr Y Nb 0 0 + o o 0 0 o + o 1 3 o o + 2 3 - - o 
Sr2YNb crystallizes in the monoclinic Cm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one Sr(2), four equivalent Sr(1), and one Y(1) atom to form a mixture of distorted edge and corner-sharing SrSr5Y octahedra. The corner-sharing octahedra are not tilted. The Sr(1)-Sr(2) bond length is 4.25 Å. All Sr(1)-Sr(1) bond lengths are 3.52 Å. The Sr(1)-Y(1) bond length is 4.31 Å. In the second Sr site, Sr(2) is bonded in a single-bond geometry to one Sr(1) and one Nb(1) atom. The Sr(2)-Nb(1) bond length is 2.16 Å. Y(1) is bonded in a distorted single-bond geometry to one Sr(1) and one Nb(1) atom. The Y(1)-Nb(1) bond length is 1.37 Å. Nb(1) is bonded in a distorted bent 120 degrees geometry to one Sr(2) and one Y(1) atom.