The structure described by Ba5Tm8Ni4O21 crystallizes in the tetragonal I4/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(1), four equivalent O(2), and four equivalent O(4) atoms. In the second Ba site, Ba(2) is bonded in a distorted q6 geometry to two equivalent O(3) and eight equivalent O(1) atoms. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one O(3), two equivalent O(2), and four equivalent O(1) atoms to form distorted TmO7 pentagonal bipyramids that share  a cornercorner with one Tm(1)O7 pentagonal bipyramid, corners with two equivalent Tm(2)O7 pentagonal bipyramids, corners with two equivalent Ni(1)O5 trigonal bipyramids, edges with three equivalent Tm(2)O7 pentagonal bipyramids, edges with two equivalent Ni(1)O5 trigonal bipyramids, and faces with two equivalent Tm(1)O7 pentagonal bipyramids. In the second Tm site, Tm(2) is bonded to one O(4), two equivalent O(1), and four equivalent O(2) atoms to form distorted TmO7 pentagonal bipyramids that share corners with two equivalent Tm(1)O7 pentagonal bipyramids, corners with two equivalent Ni(1)O5 trigonal bipyramids, edges with two equivalent Tm(2)O7 pentagonal bipyramids, edges with three equivalent Tm(1)O7 pentagonal bipyramids,  an edgeedge with one Ni(1)O5 trigonal bipyramid, and  a faceface with one Ni(1)O5 trigonal bipyramid. Ni(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form NiO5 trigonal bipyramids that share corners with two equivalent Tm(1)O7 pentagonal bipyramids, corners with two equivalent Tm(2)O7 pentagonal bipyramids,  an edgeedge with one Tm(2)O7 pentagonal bipyramid, edges with two equivalent Tm(1)O7 pentagonal bipyramids, and  a faceface with one Tm(2)O7 pentagonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ba(1), one Ba(2), one Tm(2), two equivalent Tm(1), and one Ni(1) atom to form distorted OBa2Tm3Ni octahedra that share  a cornercorner with one O(3)Ba2Tm4 octahedra, corners with three equivalent O(4)Ba4TmNi octahedra, corners with six equivalent O(1)Ba2Tm3Ni octahedra, edges with two equivalent O(1)Ba2Tm3Ni octahedra,  a faceface with one O(3)Ba2Tm4 octahedra,  a faceface with one O(4)Ba4TmNi octahedra, and faces with two equivalent O(1)Ba2Tm3Ni octahedra. The corner-sharing octahedral tilt angles range from 0-76°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Tm(1), two equivalent Tm(2), and one Ni(1) atom. In the third O site, O(3) is bonded to two equivalent Ba(2) and four equivalent Tm(1) atoms to form OBa2Tm4 octahedra that share corners with two equivalent O(3)Ba2Tm4 octahedra, corners with eight equivalent O(1)Ba2Tm3Ni octahedra, and faces with eight equivalent O(1)Ba2Tm3Ni octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the fourth O site, O(4) is bonded to four equivalent Ba(1), one Tm(2), and one Ni(1) atom to form OBa4TmNi octahedra that share corners with two equivalent O(4)Ba4TmNi octahedra, corners with six equivalent O(1)Ba2Tm3Ni octahedra, edges with five equivalent O(4)Ba4TmNi octahedra, and faces with two equivalent O(1)Ba2Tm3Ni octahedra. The corner-sharing octahedral tilt angles range from 3-62°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba5Tm8Ni4O21
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.070
_cell_length_b   10.070
_cell_length_c   10.070
_cell_angle_alpha   94.570
_cell_angle_beta   94.570
_cell_angle_gamma   147.209
_symmetry_Int_Tables_number   1
_cell_volume   530.585
_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
  Ba  Ba0  1  0.138  0.461  0.600  1.0
  Ba  Ba1  1  0.862  0.539  0.400  1.0
  Ba  Ba2  1  0.539  0.138  0.677  1.0
  Ba  Ba3  1  0.461  0.862  0.323  1.0
  Ba  Ba4  1  0.000  0.000  0.000  1.0
  Tm  Tm5  1  0.411  0.358  0.769  1.0
  Tm  Tm6  1  0.589  0.642  0.231  1.0
  Tm  Tm7  1  0.642  0.411  0.053  1.0
  Tm  Tm8  1  0.358  0.589  0.947  1.0
  Tm  Tm9  1  0.250  0.167  0.417  1.0
  Tm  Tm10  1  0.750  0.833  0.583  1.0
  Tm  Tm11  1  0.833  0.250  0.083  1.0
  Tm  Tm12  1  0.167  0.750  0.917  1.0
  Ni  Ni13  1  0.041  0.243  0.284  1.0
  Ni  Ni14  1  0.959  0.757  0.716  1.0
  Ni  Ni15  1  0.757  0.041  0.798  1.0
  Ni  Ni16  1  0.243  0.959  0.202  1.0
  O  O17  1  0.429  0.299  0.226  1.0
  O  O18  1  0.571  0.701  0.774  1.0
  O  O19  1  0.073  0.203  0.774  1.0
  O  O20  1  0.203  0.429  0.130  1.0
  O  O21  1  0.927  0.797  0.226  1.0
  O  O22  1  0.797  0.571  0.870  1.0
  O  O23  1  0.299  0.073  0.870  1.0
  O  O24  1  0.701  0.927  0.130  1.0
  O  O25  1  0.396  0.504  0.405  1.0
  O  O26  1  0.604  0.496  0.595  1.0
  O  O27  1  0.100  0.991  0.595  1.0
  O  O28  1  0.991  0.396  0.891  1.0
  O  O29  1  0.900  0.009  0.405  1.0
  O  O30  1  0.009  0.604  0.109  1.0
  O  O31  1  0.504  0.100  0.109  1.0
  O  O32  1  0.496  0.900  0.891  1.0
  O  O33  1  0.500  0.500  0.000  1.0
  O  O34  1  0.367  0.040  0.407  1.0
  O  O35  1  0.633  0.960  0.593  1.0
  O  O36  1  0.960  0.367  0.327  1.0
  O  O37  1  0.040  0.633  0.673  1.0
[/CIF]
.
The structure described by Ba5Tm8Ni4O21 crystallizes in the tetragonal I4/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(1), four equivalent O(2), and four equivalent O(4) atoms. In the second Ba site, Ba(2) is bonded in a distorted q6 geometry to two equivalent O(3) and eight equivalent O(1) atoms. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one O(3), two equivalent O(2), and four equivalent O(1) atoms to form distorted TmO7 pentagonal bipyramids that share  a cornercorner with one Tm(1)O7 pentagonal bipyramid, corners with two equivalent Tm(2)O7 pentagonal bipyramids, corners with two equivalent Ni(1)O5 trigonal bipyramids, edges with three equivalent Tm(2)O7 pentagonal bipyramids, edges with two equivalent Ni(1)O5 trigonal bipyramids, and faces with two equivalent Tm(1)O7 pentagonal bipyramids. In the second Tm site, Tm(2) is bonded to one O(4), two equivalent O(1), and four equivalent O(2) atoms to form distorted TmO7 pentagonal bipyramids that share corners with two equivalent Tm(1)O7 pentagonal bipyramids, corners with two equivalent Ni(1)O5 trigonal bipyramids, edges with two equivalent Tm(2)O7 pentagonal bipyramids, edges with three equivalent Tm(1)O7 pentagonal bipyramids,  an edgeedge with one Ni(1)O5 trigonal bipyramid, and  a faceface with one Ni(1)O5 trigonal bipyramid. Ni(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form NiO5 trigonal bipyramids that share corners with two equivalent Tm(1)O7 pentagonal bipyramids, corners with two equivalent Tm(2)O7 pentagonal bipyramids,  an edgeedge with one Tm(2)O7 pentagonal bipyramid, edges with two equivalent Tm(1)O7 pentagonal bipyramids, and  a faceface with one Tm(2)O7 pentagonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ba(1), one Ba(2), one Tm(2), two equivalent Tm(1), and one Ni(1) atom to form distorted OBa2Tm3Ni octahedra that share  a cornercorner with one O(3)Ba2Tm4 octahedra, corners with three equivalent O(4)Ba4TmNi octahedra, corners with six equivalent O(1)Ba2Tm3Ni octahedra, edges with two equivalent O(1)Ba2Tm3Ni octahedra,  a faceface with one O(3)Ba2Tm4 octahedra,  a faceface with one O(4)Ba4TmNi octahedra, and faces with two equivalent O(1)Ba2Tm3Ni octahedra. The corner-sharing octahedral tilt angles range from 0-76°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Tm(1), two equivalent Tm(2), and one Ni(1) atom. In the third O site, O(3) is bonded to two equivalent Ba(2) and four equivalent Tm(1) atoms to form OBa2Tm4 octahedra that share corners with two equivalent O(3)Ba2Tm4 octahedra, corners with eight equivalent O(1)Ba2Tm3Ni octahedra, and faces with eight equivalent O(1)Ba2Tm3Ni octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the fourth O site, O(4) is bonded to four equivalent Ba(1), one Tm(2), and one Ni(1) atom to form OBa4TmNi octahedra that share corners with two equivalent O(4)Ba4TmNi octahedra, corners with six equivalent O(1)Ba2Tm3Ni octahedra, edges with five equivalent O(4)Ba4TmNi octahedra, and faces with two equivalent O(1)Ba2Tm3Ni octahedra. The corner-sharing octahedral tilt angles range from 3-62°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba5Tm8Ni4O21
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.070
_cell_length_b   10.070
_cell_length_c   10.070
_cell_angle_alpha   94.570
_cell_angle_beta   94.570
_cell_angle_gamma   147.209
_symmetry_Int_Tables_number   1
_cell_volume   530.585
_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
  Ba  Ba0  1  0.138  0.461  0.600  1.0
  Ba  Ba1  1  0.862  0.539  0.400  1.0
  Ba  Ba2  1  0.539  0.138  0.677  1.0
  Ba  Ba3  1  0.461  0.862  0.323  1.0
  Ba  Ba4  1  0.000  0.000  0.000  1.0
  Tm  Tm5  1  0.411  0.358  0.769  1.0
  Tm  Tm6  1  0.589  0.642  0.231  1.0
  Tm  Tm7  1  0.642  0.411  0.053  1.0
  Tm  Tm8  1  0.358  0.589  0.947  1.0
  Tm  Tm9  1  0.250  0.167  0.417  1.0
  Tm  Tm10  1  0.750  0.833  0.583  1.0
  Tm  Tm11  1  0.833  0.250  0.083  1.0
  Tm  Tm12  1  0.167  0.750  0.917  1.0
  Ni  Ni13  1  0.041  0.243  0.284  1.0
  Ni  Ni14  1  0.959  0.757  0.716  1.0
  Ni  Ni15  1  0.757  0.041  0.798  1.0
  Ni  Ni16  1  0.243  0.959  0.202  1.0
  O  O17  1  0.429  0.299  0.226  1.0
  O  O18  1  0.571  0.701  0.774  1.0
  O  O19  1  0.073  0.203  0.774  1.0
  O  O20  1  0.203  0.429  0.130  1.0
  O  O21  1  0.927  0.797  0.226  1.0
  O  O22  1  0.797  0.571  0.870  1.0
  O  O23  1  0.299  0.073  0.870  1.0
  O  O24  1  0.701  0.927  0.130  1.0
  O  O25  1  0.396  0.504  0.405  1.0
  O  O26  1  0.604  0.496  0.595  1.0
  O  O27  1  0.100  0.991  0.595  1.0
  O  O28  1  0.991  0.396  0.891  1.0
  O  O29  1  0.900  0.009  0.405  1.0
  O  O30  1  0.009  0.604  0.109  1.0
  O  O31  1  0.504  0.100  0.109  1.0
  O  O32  1  0.496  0.900  0.891  1.0
  O  O33  1  0.500  0.500  0.000  1.0
  O  O34  1  0.367  0.040  0.407  1.0
  O  O35  1  0.633  0.960  0.593  1.0
  O  O36  1  0.960  0.367  0.327  1.0
  O  O37  1  0.040  0.633  0.673  1.0
[/CIF]
.