XAFS studies of local structure of functional materials with femtometer accuracy

Principal Investigator: Juris Purāns

Project duration in years: 4 (2013-2016)

Latvian Science Council Grant No.402/2012

Sychrotron Radiation X-ray Absorption Spectroscopy has undergo remarkable developments: experiments with unprecedented accuracy under extreme conditions of high pressure and temperature can nowadays be performed. Therefore, fundamental effects can be studied from new wiepoint on the local structure with femtometer accuracy (10^-5Å), that were not even conceivable just a few years ago:

1. Temperature dependent femto-XAFS studies of materials with negative thermal expansion (NTE) as ReO₃, ScF₃, ZrW₂O₈; nanoparticles and thin films as ReO₃, NiO.

2. Temperature dependent femto-XAFS studies of isotopic effect on the lattice dynamics, phase transitions and anharmonic properties of SrTiO₃, BaTiO₃, KTiO₃, ZnO.

3. In-situ femto-XAFS studies of intercaleted transition metal (TM) oxides as well as electro- and and thermochromic thin films: cathodic (WO₃, ReO₃, MoO₃, TiO₂, etc.); anodic (NiO_x, IrO_2-x); termochromic VO₂-MgO, VO₂-WO₂, VO₂-ReO₂, VO₂-IrO₂.