Phonon density of states of 57-iron and 161-dysprosium in DyFe 3 by nuclear resonant inelastic x-ray scattering under high pressure

Abstract

Phonon Density of States of 57-Iron and 161-Dysprosium in DyFe3 By Nuclear Resonant Inelastic X-Ray Scattering Under Pressure by Elizabeth Anne Tanis Dr. Lon Spight, Examination Committee Chair Professor of Physics University of Nevada, Las Vegas The dual partial phonon density of states (DOS) from two different Mossbauer isotopes (Dy and Fe) in the same material (dyfe3) was successfully measured using the nuclear resonant inelastic x-ray scattering (NRIXS) technique at high pressure. Nuclear inelastic scattering measurements yield an in-depth understanding of the element-specific dynamic properties. The Debye temperatures (ΘD), the LambMossbauer factor (fLM), and the vibrational contributions to the Helmholtz free energy (Fvib), specific heat (cV ), entropy (Svib) and internal energy (Uvib) are calculated directly from the phonon density of states.