(YFe3F14)2F2 crystallizes in the monoclinic P2_1/m space group. The structure consists of two hydrofluoric acid atoms inside a YFe3F14 framework. In the YFe3F14 framework, Y(1) is bonded to one F(1), one F(3), two equivalent F(5), and two equivalent F(8) atoms to form YF6 octahedra that share corners with two equivalent Fe(1)F6 octahedra and corners with four equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 8-52°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent F(4), two equivalent F(5), and two equivalent F(7) atoms to form FeF6 octahedra that share corners with two equivalent Y(1)F6 octahedra and edges with two equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles are 45°. In the second Fe site, Fe(2) is bonded to one F(4), one F(5), one F(8), one F(9), and two equivalent F(6) atoms to form FeF6 octahedra that share corners with two equivalent Y(1)F6 octahedra,  an edgeedge with one Fe(1)F6 octahedra, and  an edgeedge with one Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 8-52°. There are eight inequivalent F sites. In the first F site, F(1) is bonded in a single-bond geometry to one Y(1) atom. In the second F site, F(3) is bonded in a single-bond geometry to one Y(1) atom. In the third F site, F(4) is bonded in a water-like geometry to one Fe(1) and one Fe(2) atom. In the fourth F site, F(5) is bonded in a distorted trigonal planar geometry to one Y(1), one Fe(1), and one Fe(2) atom. In the fifth F site, F(6) is bonded in a water-like geometry to two equivalent Fe(2) atoms. In the sixth F site, F(7) is bonded in a single-bond geometry to one Fe(1) atom. In the seventh F site, F(8) is bonded in a linear geometry to one Y(1) and one Fe(2) atom. In the eighth F site, F(9) is bonded in a single-bond geometry to one Fe(2) atom.
(YFe3F14)2F2 crystallizes in the monoclinic P2_1/m space group. The structure consists of two hydrofluoric acid atoms inside a YFe3F14 framework. In the YFe3F14 framework, Y(1) is bonded to one F(1), one F(3), two equivalent F(5), and two equivalent F(8) atoms to form YF6 octahedra that share corners with two equivalent Fe(1)F6 octahedra and corners with four equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 8-52°. The Y(1)-F(1) bond length is 2.17 Å. The Y(1)-F(3) bond length is 2.06 Å. Both Y(1)-F(5) bond lengths are 2.42 Å. Both Y(1)-F(8) bond lengths are 2.19 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent F(4), two equivalent F(5), and two equivalent F(7) atoms to form FeF6 octahedra that share corners with two equivalent Y(1)F6 octahedra and edges with two equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles are 45°. Both Fe(1)-F(4) bond lengths are 1.88 Å. Both Fe(1)-F(5) bond lengths are 2.09 Å. Both Fe(1)-F(7) bond lengths are 1.76 Å. In the second Fe site, Fe(2) is bonded to one F(4), one F(5), one F(8), one F(9), and two equivalent F(6) atoms to form FeF6 octahedra that share corners with two equivalent Y(1)F6 octahedra,  an edgeedge with one Fe(1)F6 octahedra, and  an edgeedge with one Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 8-52°. The Fe(2)-F(4) bond length is 2.03 Å. The Fe(2)-F(5) bond length is 2.17 Å. The Fe(2)-F(8) bond length is 1.95 Å. The Fe(2)-F(9) bond length is 1.80 Å. Both Fe(2)-F(6) bond lengths are 1.97 Å. There are eight inequivalent F sites. In the first F site, F(1) is bonded in a single-bond geometry to one Y(1) atom. In the second F site, F(3) is bonded in a single-bond geometry to one Y(1) atom. In the third F site, F(4) is bonded in a water-like geometry to one Fe(1) and one Fe(2) atom. In the fourth F site, F(5) is bonded in a distorted trigonal planar geometry to one Y(1), one Fe(1), and one Fe(2) atom. In the fifth F site, F(6) is bonded in a water-like geometry to two equivalent Fe(2) atoms. In the sixth F site, F(7) is bonded in a single-bond geometry to one Fe(1) atom. In the seventh F site, F(8) is bonded in a linear geometry to one Y(1) and one Fe(2) atom. In the eighth F site, F(9) is bonded in a single-bond geometry to one Fe(2) atom.