Student: Samantha Combs (Eckerd College)

Mentor: Malcolm Nicol

Phonon Density of States of Iron Solid Solutions at Ambient and High Pressures Using Nuclear Resonant Inelastic X-ray Scattering (NRIXS)

Nuclear resonant inelastic x-ray scattering (NRIXS) of synchrotron radiation uses the energy transferred during the inelastic nuclear absorption of photons to determine phonon density of states for solid Mossbauer isotopes. This type of experiment can be conducted at ambient and high pressure with the use of a diamond anvil cell (DAC) and a rhenium gasket. Here, we are concerned with the phonon density of states of alpha-FePt 10% at pressures up to 30 GPa, as well as FeAl 4.3%, 6.4%, and 27.1% at ambient pressures.The iron samples used are doped in order to increase the pressure at which the alpha to epsilon phase transition for iron occurs. As the most abundant element within the core of the Earth, the study of iron is fundamental in geophysics and for thermodynamic modeling.