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CrB2 is hexagonal omega structure structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Cr6+ is bonded to twelve equivalent B3- atoms to form a mixture of edge and face-sharing CrB12 cuboctahedra. All Cr–B bond lengths are 2.28 Å. B3- is bonded in a 9-coordinate geometry to six equivalent Cr6+ and three equivalent B3- atoms. All B–B bond lengths are 1.71 Å.
CrB2(PbO2)6 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Cr6+ is bonded to four O2- atoms to form CrO4 tetrahedra that share corners with four equivalent PbO5 square pyramids. There is three shorter (1.67 Å) and one longer (1.70 Å) Cr–O bond length. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.38–1.40 Å. There are four inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Pb–O bond distances ranging from 2.40–3.04 Å. In the second Pb2+ site, Pb2+ is bonded to five O2- atoms to form distorted PbO5 square pyramids that share corners with two equivalent CrO4 tetrahedra and an edgeedge with one PbO5 square pyramid. There are a spread of Pb–O bond distances ranging from 2.22–3.09 Å. In the third Pb2+ site, Pb2+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Pb–O bond distances ranging from 2.21–2.82 Å. In the fourth Pb2+ site, Pb2+ is bonded in a 4-coordinate geometry to seven O2- atoms. There are a spread of Pb–O bond distances ranging from 2.33–3.07 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to four Pb2+ atoms. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one B3+ and three Pb2+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one Cr6+ and three Pb2+ atoms. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Cr6+ and three Pb2+ atoms. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one B3+ and two Pb2+ atoms. In the sixth O2- site, O2- is bonded to four Pb2+ atoms to form distorted corner-sharing OPb4 tetrahedra. In the seventh O2- site, O2- is bonded in a single-bond geometry to one Cr6+ and one Pb2+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one B3+ and three Pb2+ atoms.