Interstitialcy model for condensed matter states of face-centered-cubic metals

The special configuration and dynamics known for interstitialcies in face-centered-cubic metals are exploited to construct a model giving all the thermodynamic properties of crystalline, liquid, and amorphous states in a unified way. A large diaelastic softening of the shear modulus with defect concentration is derived. This leads to a softening of the interstitialcy formation energy, which, taken together with a large entropy contribution from the interstitialcy resonance modes, makes the model, which contains Lindemann's law, viable for quantitative calculations of thermodynamic properties.