High-Resolution Inelastic X-ray Scattering
High-resolution Inelastic X-ray Scattering (IXS) techniques provide the Earth and planetary science community with opportunities for new and exciting results on the properties of materials at high pressure and temperature conditions. Such experiments have become possible due to the characteristics of third-generation synchrotron radiation sources such as the Advanced Photon Source. The techniques fall into three broad areas:
- Momentum-resolved Inelastic X-ray Scattering directly gives the dispersion relation of low-energy collective excitations like phonons. Such measurements provide directional information on vibrational and elastic properties, such as the elastic tensor and sound velocities.
- Synchrotron Mössbauer Spectroscopy (SMS) provides information on magnetic properties and valence state of iron in minerals and high-pressure phases. It is also sensitive to solid-melt transitions.
- Nuclear Resonant Inelastic X-ray Scattering (NRIXS) provides information on vibrational and elastic properties, such as the phonon density of states and sound velocities. These methods are in many ways ideally or even uniquely suited for addressing a number of important geophysical questions.