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HfTc is Tetraauricupride structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Hf is bonded in a body-centered cubic geometry to eight equivalent Tc atoms. All Hf–Tc bond lengths are 2.83 Å. Tc is bonded in a body-centered cubic geometry to eight equivalent Hf atoms.
HfTc2 is Hexagonal Laves structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Hf4+ is bonded in a 12-coordinate geometry to twelve Tc2- atoms. There are a spread of Hf–Tc bond distances ranging from 3.05–3.09 Å. There are three inequivalent Tc2- sites. In the first Tc2- site, Tc2- is bonded to six equivalent Hf4+ and six Tc2- atoms to form a mixture of edge, face, and corner-sharing TcHf6Tc6 cuboctahedra. There are a spread of Tc–Tc bond distances ranging from 2.51–2.68 Å. In the second Tc2- site, Tc2- is bonded to six equivalent Hf4+ and six Tc2- atoms to form a mixture of edge, face, and corner-sharing TcHf6Tc6 cuboctahedra. Both Tc–Tc bond lengths are 2.68 Å. In the third Tc2- site, Tc2- is bonded to six equivalent Hf4+ and six Tc2- atoms to form a mixture of edge, face, and corner-sharing TcHf6Tc6 cuboctahedra.