Publications Details

Molecular Origins of Temperature-Dependent X-ray Absorption in YAG:Dy

Vogel, Dayton J.; Rimsza, Jessica M.; Hansen, Linda E.; Westphal, Eric R.; Winters, Caroline

The absorption and emission of X-rays in dysprosium-doped yttrium aluminum garnet (YAG:Dy) has produced unexpected thermographic behavior, which is investigated using a combination of finite temperature ab initio molecular dynamic simulations, structural characterization, and electronic structure calculations of X-ray characteristics. Calculated average peak X-ray absorption spectra (XAS) from simulations between 300 and 600 K result in peak intensity loss due to thermalization effects, matching experimentally measured behavior of YAG:Dy. Investigation of atomic snapshots indicates structural factors that correlated with the X-ray behavior, with the first Y-O coordination sphere identified as the primary structural feature unique to high XAS intensity as calculated by radial and pair distribution functions.