DOE OSTI2020
RbBiF4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are three inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded to five F1- atoms to form distorted RbF5 trigonal bipyramids that share corners with six equivalent RbF5 trigonal bipyramids and corners with three equivalent RbF4 trigonal pyramids. There are a spread of Rb–F bond distances ranging from 2.63–2.86 Å. In the second Rb1+ site, Rb1+ is bonded to four F1- atoms to form RbF4 trigonal pyramids that share corners with three equivalent RbF5 trigonal bipyramids and corners with six equivalent RbF4 trigonal pyramids. There are a spread of Rb–F bond distances ranging from 2.62–2.84 Å. In the third Rb1+ site, Rb1+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Rb–F bond distances ranging from 2.79–3.30 Å. There are three inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Bi–F bond distances ranging from 2.18–2.68 Å. In the second Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Bi–F bond distances ranging from 2.13–2.86 Å. In the third Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Bi–F bond distances ranging from 2.18–2.71 Å. There are twelve inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to one Rb1+ and two equivalent Bi3+ atoms. In the second F1- site, F1- is bonded to three equivalent Rb1+ and one Bi3+ atom to form distorted corner-sharing FRb3Bi tetrahedra. In the third F1- site, F1- is bonded to four Rb1+ atoms to form corner-sharing FRb4 tetrahedra. In the fourth F1- site, F1- is bonded in a 2-coordinate geometry to two equivalent Bi3+ atoms. In the fifth F1- site, F1- is bonded to four Rb1+ atoms to form corner-sharing FRb4 trigonal pyramids. In the sixth F1- site, F1- is bonded in a 1-coordinate geometry to three equivalent Rb1+ and one Bi3+ atom. In the seventh F1- site, F1- is bonded in a 1-coordinate geometry to one Rb1+ and two equivalent Bi3+ atoms. In the eighth F1- site, F1- is bonded in a 1-coordinate geometry to three Bi3+ atoms. In the ninth F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two Bi3+ atoms. In the tenth F1- site, F1- is bonded in a 1-coordinate geometry to three Bi3+ atoms. In the eleventh F1- site, F1- is bonded in a bent 120 degrees geometry to two Bi3+ atoms. In the twelfth F1- site, F1- is bonded in a bent 150 degrees geometry to two equivalent Bi3+ atoms.