DOE OSTI2020
Cu5As2(HO3)4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Cu–O bond distances ranging from 1.96–2.78 Å. In the second Cu2+ site, Cu2+ is bonded to six O2- atoms to form distorted CuO6 octahedra that share corners with three equivalent AsO4 tetrahedra and an edgeedge with one CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.93–2.56 Å. In the third Cu2+ site, Cu2+ is bonded in a distorted square co-planar geometry to four O2- atoms. There is two shorter (1.94 Å) and two longer (2.03 Å) Cu–O bond length. As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with three equivalent CuO6 octahedra. The corner-sharing octahedra tilt angles range from 9–67°. There are a spread of As–O bond distances ranging from 1.69–1.76 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two Cu2+ and one As5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three Cu2+ and one H1+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two Cu2+ and one As5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Cu2+ and one As5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Cu2+ and one As5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to three Cu2+ and one H1+ atom.