NbSeF9 is alpha Po structured and crystallizes in the trigonal R3 space group. The structure is zero-dimensional and consists of three NbSeF9 clusters. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one F(10), one F(11), one F(2), one F(3), one F(6), and one F(7) atom to form NbF6 octahedra that share  a cornercorner with one Se(2)F6 octahedra and corners with two equivalent Se(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 1-5°. In the second Nb site, Nb(2) is bonded to three equivalent F(4) and three equivalent F(5) atoms to form NbF6 octahedra that share corners with three equivalent Se(1)F6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one F(1), one F(11), one F(3), one F(5), one F(8), and one F(9) atom to form distorted SeF6 octahedra that share  a cornercorner with one Nb(2)F6 octahedra and corners with two equivalent Nb(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 1-5°. In the second Se site, Se(2) is bonded to three equivalent F(12) and three equivalent F(2) atoms to form distorted SeF6 octahedra that share corners with three equivalent Nb(1)F6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are twelve inequivalent F sites. In the first F site, F(4) is bonded in a single-bond geometry to one Nb(2) atom. In the second F site, F(5) is bonded in a linear geometry to one Nb(2) and one Se(1) atom. In the third F site, F(6) is bonded in a single-bond geometry to one Nb(1) atom. In the fourth F site, F(7) is bonded in a single-bond geometry to one Nb(1) atom. In the fifth F site, F(8) is bonded in a single-bond geometry to one Se(1) atom. In the sixth F site, F(9) is bonded in a single-bond geometry to one Se(1) atom. In the seventh F site, F(10) is bonded in a single-bond geometry to one Nb(1) atom. In the eighth F site, F(11) is bonded in a linear geometry to one Nb(1) and one Se(1) atom. In the ninth F site, F(12) is bonded in a single-bond geometry to one Se(2) atom. In the tenth F site, F(1) is bonded in a single-bond geometry to one Se(1) atom. In the eleventh F site, F(2) is bonded in a linear geometry to one Nb(1) and one Se(2) atom. In the twelfth F site, F(3) is bonded in a distorted linear geometry to one Nb(1) and one Se(1) atom.
NbSeF9 is alpha Po structured and crystallizes in the trigonal R3 space group. The structure is zero-dimensional and consists of three NbSeF9 clusters. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one F(10), one F(11), one F(2), one F(3), one F(6), and one F(7) atom to form NbF6 octahedra that share  a cornercorner with one Se(2)F6 octahedra and corners with two equivalent Se(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 1-5°. The Nb(1)-F(10) bond length is 1.88 Å. The Nb(1)-F(11) bond length is 1.99 Å. The Nb(1)-F(2) bond length is 1.99 Å. The Nb(1)-F(3) bond length is 1.98 Å. The Nb(1)-F(6) bond length is 1.88 Å. The Nb(1)-F(7) bond length is 1.89 Å. In the second Nb site, Nb(2) is bonded to three equivalent F(4) and three equivalent F(5) atoms to form NbF6 octahedra that share corners with three equivalent Se(1)F6 octahedra. The corner-sharing octahedral tilt angles are 3°. All Nb(2)-F(4) bond lengths are 1.88 Å. All Nb(2)-F(5) bond lengths are 1.99 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one F(1), one F(11), one F(3), one F(5), one F(8), and one F(9) atom to form distorted SeF6 octahedra that share  a cornercorner with one Nb(2)F6 octahedra and corners with two equivalent Nb(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 1-5°. The Se(1)-F(1) bond length is 1.71 Å. The Se(1)-F(11) bond length is 2.32 Å. The Se(1)-F(3) bond length is 2.37 Å. The Se(1)-F(5) bond length is 2.33 Å. The Se(1)-F(8) bond length is 1.71 Å. The Se(1)-F(9) bond length is 1.71 Å. In the second Se site, Se(2) is bonded to three equivalent F(12) and three equivalent F(2) atoms to form distorted SeF6 octahedra that share corners with three equivalent Nb(1)F6 octahedra. The corner-sharing octahedral tilt angles are 3°. All Se(2)-F(12) bond lengths are 1.71 Å. All Se(2)-F(2) bond lengths are 2.33 Å. There are twelve inequivalent F sites. In the first F site, F(4) is bonded in a single-bond geometry to one Nb(2) atom. In the second F site, F(5) is bonded in a linear geometry to one Nb(2) and one Se(1) atom. In the third F site, F(6) is bonded in a single-bond geometry to one Nb(1) atom. In the fourth F site, F(7) is bonded in a single-bond geometry to one Nb(1) atom. In the fifth F site, F(8) is bonded in a single-bond geometry to one Se(1) atom. In the sixth F site, F(9) is bonded in a single-bond geometry to one Se(1) atom. In the seventh F site, F(10) is bonded in a single-bond geometry to one Nb(1) atom. In the eighth F site, F(11) is bonded in a linear geometry to one Nb(1) and one Se(1) atom. In the ninth F site, F(12) is bonded in a single-bond geometry to one Se(2) atom. In the tenth F site, F(1) is bonded in a single-bond geometry to one Se(1) atom. In the eleventh F site, F(2) is bonded in a linear geometry to one Nb(1) and one Se(2) atom. In the twelfth F site, F(3) is bonded in a distorted linear geometry to one Nb(1) and one Se(1) atom.