Thursday, April 26, 20122:00 PM - 3:00 PMCNLS Conference Room (TA-3, Bldg 1690)|
A new methodology to uncover the true atomic structure of complex materials
Claire WhiteT-1 and CNLS
Ordinary Portland cement-based (OPC) concrete is the most used building material world-wide and is the 2nd most used resource, after water. However, concrete is the 3rd highest CO2 emitter, accounting for 5-8% of all man-made emissions, and therefore there is massive scope for technological development of alternative concretes. Here, a new methodology to elucidate accurate structural representations of complex materials will be outlined, which combines total scattering and computational chemistry. The disordered aluminosilicate material, metakaolin, an alternative cement precursor, will be used as the case study, and it will be shown that the methodology reveals the existence of III-coordinated aluminum, which has never before been shown to exist in this material. This research exemplified the power of combining local structural data (i.e., neutron pair distribution function analysis) with first-principles calculations for amorphous materials, especially when used in an iterative manner to maintain thermodynamic feasibility and agreement with experimental data.
Host: Kipton Barros, T-4 and CNLS