Materials Data on Rb2Be2Si2O7 by Materials Project
Rb2Be2Si2O7 crystallizes in the orthorhombic Pnn2 space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 2-coordinate geometry to ten O2- atoms. There are a spread of Rb–O bond distances ranging from 2.91–3.38 Å. In the second Rb1+ site, Rb1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Rb–O bond distances ranging from 2.95–3.21 Å. Be2+ is bonded in a trigonal planar geometry to three O2- atoms. All Be–O bond lengths are 1.54 Å. Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There is three shorter (1.63 Å) and one longer (1.66 Å) Si–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to three Rb1+, one Be2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Rb1+, one Be2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Rb1+, one Be2+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a linear geometry to two equivalent Rb1+ and two equivalent Si4+ atoms.