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Hafnia (HfO2) is a technologically important hard material with a relatively high dielectric constant and wide band gap [1]. However, the basic properties of HfO2 have been little studied in the literature due to its close resemblance to zirconia in chemical properties. In the bulk, the monoclinic (space group: P21/c) phase represents the thermodynamic minimum; phase transformation to a distorted fluorite tetragonal (space group: P42/nmc) phase is induced upon heating to 1720oC.[2] The symmetry-lowering tetragonal to monoclinic phase transition in HfO2 closely parallels the better studied phase transition in ZrO2 and is believed to be Martensitic and athermal in nature. The transformation is thought to proceed through a diffusionless process wherein bond distances and angles are altered without disrupting the atomic connectivity within the lattice with preservation of a mirror plane symmetry element. Similar to ZrO2 …