Rb2FeF5 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 10-coordinate geometry to two equivalent F(2), two equivalent F(3), two equivalent F(4), and four equivalent F(1) atoms. In the second Rb site, Rb(2) is bonded in a 10-coordinate geometry to two equivalent F(2), two equivalent F(3), two equivalent F(4), and four equivalent F(1) atoms. Fe(1) is bonded to one F(2), one F(4), two equivalent F(1), and two equivalent F(3) atoms to form corner-sharing FeF6 octahedra. The corner-sharing octahedra are not tilted. There are four inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to two equivalent Rb(1), two equivalent Rb(2), and one Fe(1) atom. In the second F site, F(2) is bonded in a 1-coordinate geometry to two equivalent Rb(1), two equivalent Rb(2), and one Fe(1) atom. In the third F site, F(3) is bonded in a linear geometry to two equivalent Rb(1), two equivalent Rb(2), and two equivalent Fe(1) atoms. In the fourth F site, F(4) is bonded in a distorted single-bond geometry to two equivalent Rb(1), two equivalent Rb(2), and one Fe(1) atom.
Rb2FeF5 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 10-coordinate geometry to two equivalent F(2), two equivalent F(3), two equivalent F(4), and four equivalent F(1) atoms. There is one shorter (2.80 Å) and one longer (2.81 Å) Rb(1)-F(2) bond length. Both Rb(1)-F(3) bond lengths are 3.04 Å. Both Rb(1)-F(4) bond lengths are 2.92 Å. There are two shorter (2.87 Å) and two longer (2.97 Å) Rb(1)-F(1) bond lengths. In the second Rb site, Rb(2) is bonded in a 10-coordinate geometry to two equivalent F(2), two equivalent F(3), two equivalent F(4), and four equivalent F(1) atoms. Both Rb(2)-F(2) bond lengths are 2.94 Å. Both Rb(2)-F(3) bond lengths are 3.13 Å. There is one shorter (2.87 Å) and one longer (2.98 Å) Rb(2)-F(4) bond length. There are two shorter (2.87 Å) and two longer (2.96 Å) Rb(2)-F(1) bond lengths. Fe(1) is bonded to one F(2), one F(4), two equivalent F(1), and two equivalent F(3) atoms to form corner-sharing FeF6 octahedra. The corner-sharing octahedra are not tilted. The Fe(1)-F(2) bond length is 1.93 Å. The Fe(1)-F(4) bond length is 1.90 Å. Both Fe(1)-F(1) bond lengths are 1.89 Å. Both Fe(1)-F(3) bond lengths are 2.05 Å. There are four inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to two equivalent Rb(1), two equivalent Rb(2), and one Fe(1) atom. In the second F site, F(2) is bonded in a 1-coordinate geometry to two equivalent Rb(1), two equivalent Rb(2), and one Fe(1) atom. In the third F site, F(3) is bonded in a linear geometry to two equivalent Rb(1), two equivalent Rb(2), and two equivalent Fe(1) atoms. In the fourth F site, F(4) is bonded in a distorted single-bond geometry to two equivalent Rb(1), two equivalent Rb(2), and one Fe(1) atom.