This work complements our recent discovery of new phases derived from zirconium perchlorate by addition of hydrogen peroxide. Here, we investigate analogous reactions with hafnium perchlorate, which is found to have modifications of the Clearfield-Vaughan tetramer (CVT). For hafnium perchlorate derivatives, we find distorted versions of CVT by X-ray diffraction and study the reaction solutions by SAXS, Raman spectroscopy, and ESI-MS. Furthermore, we investigate mixed Hf-Zr solution and solid phases and find the latter resemble the zirconium family at low Hf concentrations and the hafnium family at higher hafnium contents.