Materials Data on K2Pu2O5 by Materials Project
K2Pu2O5 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All K–O bond lengths are 2.86 Å. In the second K1+ site, K1+ is bonded to twelve O2- atoms to form KO12 cuboctahedra that share corners with four equivalent KO12 cuboctahedra, faces with four equivalent KO12 cuboctahedra, and faces with eight equivalent PuO5 square pyramids. There are four shorter (3.04 Å) and eight longer (3.25 Å) K–O bond lengths. Pu4+ is bonded to five O2- atoms to form PuO5 square pyramids that share corners with five equivalent PuO5 square pyramids and faces with four equivalent KO12 cuboctahedra. There are one shorter (2.15 Å) and four longer (2.17 Å) Pu–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to four K1+ and two equivalent Pu4+ atoms. In the second O2- site, O2- is bonded to four equivalent K1+ and two equivalent Pu4+ atoms to form a mixture of distorted corner and edge-sharing OK4Pu2 octahedra. The corner-sharing octahedral tilt angles are 0°.