The material structure described by Ba2Ni7F18 crystallizes in the triclinic P-1 space group. Ba(1) is bonded to one F(1), one F(2), one F(4), one F(7), two equivalent F(3), two equivalent F(6), two equivalent F(8), and two equivalent F(9) atoms to form BaF12 cuboctahedra that share  a cornercorner with one Ni(2)F6 octahedra, corners with two equivalent Ni(1)F6 octahedra, corners with two equivalent Ni(3)F6 octahedra, corners with two equivalent Ni(4)F6 octahedra, edges with two equivalent Ba(1)F12 cuboctahedra,  an edgeedge with one Ni(2)F6 octahedra,  an edgeedge with one Ni(3)F6 octahedra,  an edgeedge with one Ni(4)F6 octahedra, edges with two equivalent Ni(1)F6 octahedra,  a faceface with one Ba(1)F12 cuboctahedra,  a faceface with one Ni(3)F6 octahedra, and faces with two equivalent Ni(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 28-53°. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one F(2), one F(4), one F(5), one F(6), and two equivalent F(1) atoms to form NiF6 octahedra that share corners with two equivalent Ba(1)F12 cuboctahedra,  a cornercorner with one Ni(4)F6 octahedra, corners with three equivalent Ni(3)F6 octahedra, edges with two equivalent Ba(1)F12 cuboctahedra,  an edgeedge with one Ni(1)F6 octahedra, and edges with two equivalent Ni(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 48-53°. In the second Ni site, Ni(2) is bonded to one F(1), one F(3), one F(4), one F(6), one F(7), and one F(9) atom to form NiF6 octahedra that share  a cornercorner with one Ba(1)F12 cuboctahedra,  a cornercorner with one Ni(4)F6 octahedra, corners with three equivalent Ni(3)F6 octahedra,  an edgeedge with one Ba(1)F12 cuboctahedra, edges with two equivalent Ni(1)F6 octahedra, and faces with two equivalent Ba(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 51-54°. In the third Ni site, Ni(3) is bonded to one F(2), one F(3), one F(4), one F(5), one F(7), and one F(8) atom to form NiF6 octahedra that share corners with two equivalent Ba(1)F12 cuboctahedra, corners with three equivalent Ni(1)F6 octahedra, corners with three equivalent Ni(2)F6 octahedra,  an edgeedge with one Ba(1)F12 cuboctahedra,  an edgeedge with one Ni(4)F6 octahedra, and  a faceface with one Ba(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 48-54°. In the fourth Ni site, Ni(4) is bonded to two equivalent F(5), two equivalent F(8), and two equivalent F(9) atoms to form NiF6 octahedra that share corners with four equivalent Ba(1)F12 cuboctahedra, corners with two equivalent Ni(1)F6 octahedra, corners with two equivalent Ni(2)F6 octahedra, edges with two equivalent Ba(1)F12 cuboctahedra, and edges with two equivalent Ni(3)F6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. There are nine inequivalent F sites. In the first F site, F(1) is bonded in a 3-coordinate geometry to one Ba(1), one Ni(2), and two equivalent Ni(1) atoms. In the second F site, F(2) is bonded in a 3-coordinate geometry to one Ba(1), one Ni(1), and one Ni(3) atom. In the third F site, F(3) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(1), one Ni(2), and one Ni(3) atom. In the fourth F site, F(4) is bonded in a 3-coordinate geometry to one Ba(1), one Ni(1), one Ni(2), and one Ni(3) atom. In the fifth F site, F(5) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(3), and one Ni(4) atom. In the sixth F site, F(6) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Ni(1), and one Ni(2) atom. In the seventh F site, F(7) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ni(2), and one Ni(3) atom. In the eighth F site, F(8) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Ni(3), and one Ni(4) atom. In the ninth F site, F(9) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(1), one Ni(2), and one Ni(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2Ni7F18
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.004
_cell_length_b   7.312
_cell_length_c   7.555
_cell_angle_alpha   94.439
_cell_angle_beta   93.103
_cell_angle_gamma   115.767
_symmetry_Int_Tables_number   1
_cell_volume   345.742
_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  0.686  0.306  0.366  1.0
  Ba  Ba1  1  0.314  0.694  0.634  1.0
  Ni  Ni2  1  0.394  0.278  0.882  1.0
  Ni  Ni3  1  0.606  0.722  0.118  1.0
  Ni  Ni4  1  0.181  0.384  0.195  1.0
  Ni  Ni5  1  0.819  0.616  0.805  1.0
  Ni  Ni6  1  0.810  0.125  0.818  1.0
  Ni  Ni7  1  0.190  0.875  0.182  1.0
  Ni  Ni8  1  0.000  0.000  0.500  1.0
  F  F9  1  0.319  0.512  0.974  1.0
  F  F10  1  0.681  0.488  0.026  1.0
  F  F11  1  0.504  0.078  0.817  1.0
  F  F12  1  0.496  0.922  0.183  1.0
  F  F13  1  0.900  0.395  0.719  1.0
  F  F14  1  0.100  0.605  0.281  1.0
  F  F15  1  0.294  0.174  0.119  1.0
  F  F16  1  0.706  0.826  0.881  1.0
  F  F17  1  0.098  0.128  0.758  1.0
  F  F18  1  0.479  0.559  0.321  1.0
  F  F19  1  0.521  0.441  0.679  1.0
  F  F20  1  0.108  0.770  0.927  1.0
  F  F21  1  0.892  0.230  0.073  1.0
  F  F22  1  0.718  0.993  0.559  1.0
  F  F23  1  0.282  0.007  0.441  1.0
  F  F24  1  0.922  0.719  0.575  1.0
  F  F25  1  0.078  0.281  0.425  1.0
  F  F26  1  0.902  0.872  0.242  1.0
[/CIF]
.
The material structure described by Ba2Ni7F18 crystallizes in the triclinic P-1 space group. Ba(1) is bonded to one F(1), one F(2), one F(4), one F(7), two equivalent F(3), two equivalent F(6), two equivalent F(8), and two equivalent F(9) atoms to form BaF12 cuboctahedra that share  a cornercorner with one Ni(2)F6 octahedra, corners with two equivalent Ni(1)F6 octahedra, corners with two equivalent Ni(3)F6 octahedra, corners with two equivalent Ni(4)F6 octahedra, edges with two equivalent Ba(1)F12 cuboctahedra,  an edgeedge with one Ni(2)F6 octahedra,  an edgeedge with one Ni(3)F6 octahedra,  an edgeedge with one Ni(4)F6 octahedra, edges with two equivalent Ni(1)F6 octahedra,  a faceface with one Ba(1)F12 cuboctahedra,  a faceface with one Ni(3)F6 octahedra, and faces with two equivalent Ni(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 28-53°. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one F(2), one F(4), one F(5), one F(6), and two equivalent F(1) atoms to form NiF6 octahedra that share corners with two equivalent Ba(1)F12 cuboctahedra,  a cornercorner with one Ni(4)F6 octahedra, corners with three equivalent Ni(3)F6 octahedra, edges with two equivalent Ba(1)F12 cuboctahedra,  an edgeedge with one Ni(1)F6 octahedra, and edges with two equivalent Ni(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 48-53°. In the second Ni site, Ni(2) is bonded to one F(1), one F(3), one F(4), one F(6), one F(7), and one F(9) atom to form NiF6 octahedra that share  a cornercorner with one Ba(1)F12 cuboctahedra,  a cornercorner with one Ni(4)F6 octahedra, corners with three equivalent Ni(3)F6 octahedra,  an edgeedge with one Ba(1)F12 cuboctahedra, edges with two equivalent Ni(1)F6 octahedra, and faces with two equivalent Ba(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 51-54°. In the third Ni site, Ni(3) is bonded to one F(2), one F(3), one F(4), one F(5), one F(7), and one F(8) atom to form NiF6 octahedra that share corners with two equivalent Ba(1)F12 cuboctahedra, corners with three equivalent Ni(1)F6 octahedra, corners with three equivalent Ni(2)F6 octahedra,  an edgeedge with one Ba(1)F12 cuboctahedra,  an edgeedge with one Ni(4)F6 octahedra, and  a faceface with one Ba(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles range from 48-54°. In the fourth Ni site, Ni(4) is bonded to two equivalent F(5), two equivalent F(8), and two equivalent F(9) atoms to form NiF6 octahedra that share corners with four equivalent Ba(1)F12 cuboctahedra, corners with two equivalent Ni(1)F6 octahedra, corners with two equivalent Ni(2)F6 octahedra, edges with two equivalent Ba(1)F12 cuboctahedra, and edges with two equivalent Ni(3)F6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. There are nine inequivalent F sites. In the first F site, F(1) is bonded in a 3-coordinate geometry to one Ba(1), one Ni(2), and two equivalent Ni(1) atoms. In the second F site, F(2) is bonded in a 3-coordinate geometry to one Ba(1), one Ni(1), and one Ni(3) atom. In the third F site, F(3) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(1), one Ni(2), and one Ni(3) atom. In the fourth F site, F(4) is bonded in a 3-coordinate geometry to one Ba(1), one Ni(1), one Ni(2), and one Ni(3) atom. In the fifth F site, F(5) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(3), and one Ni(4) atom. In the sixth F site, F(6) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Ni(1), and one Ni(2) atom. In the seventh F site, F(7) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ni(2), and one Ni(3) atom. In the eighth F site, F(8) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Ni(3), and one Ni(4) atom. In the ninth F site, F(9) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(1), one Ni(2), and one Ni(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2Ni7F18
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.004
_cell_length_b   7.312
_cell_length_c   7.555
_cell_angle_alpha   94.439
_cell_angle_beta   93.103
_cell_angle_gamma   115.767
_symmetry_Int_Tables_number   1
_cell_volume   345.742
_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  0.686  0.306  0.366  1.0
  Ba  Ba1  1  0.314  0.694  0.634  1.0
  Ni  Ni2  1  0.394  0.278  0.882  1.0
  Ni  Ni3  1  0.606  0.722  0.118  1.0
  Ni  Ni4  1  0.181  0.384  0.195  1.0
  Ni  Ni5  1  0.819  0.616  0.805  1.0
  Ni  Ni6  1  0.810  0.125  0.818  1.0
  Ni  Ni7  1  0.190  0.875  0.182  1.0
  Ni  Ni8  1  0.000  0.000  0.500  1.0
  F  F9  1  0.319  0.512  0.974  1.0
  F  F10  1  0.681  0.488  0.026  1.0
  F  F11  1  0.504  0.078  0.817  1.0
  F  F12  1  0.496  0.922  0.183  1.0
  F  F13  1  0.900  0.395  0.719  1.0
  F  F14  1  0.100  0.605  0.281  1.0
  F  F15  1  0.294  0.174  0.119  1.0
  F  F16  1  0.706  0.826  0.881  1.0
  F  F17  1  0.098  0.128  0.758  1.0
  F  F18  1  0.479  0.559  0.321  1.0
  F  F19  1  0.521  0.441  0.679  1.0
  F  F20  1  0.108  0.770  0.927  1.0
  F  F21  1  0.892  0.230  0.073  1.0
  F  F22  1  0.718  0.993  0.559  1.0
  F  F23  1  0.282  0.007  0.441  1.0
  F  F24  1  0.922  0.719  0.575  1.0
  F  F25  1  0.078  0.281  0.425  1.0
  F  F26  1  0.902  0.872  0.242  1.0
[/CIF]
.