Understanding Bioactive Glasses at the Atomic Scale: the Complementary use of Advanced Probe and Computer Modelling Methods

Sol-gel synthesised bioactive glasses may be formed via a hydrolysis condensation reaction, silica being introduced in the form of tetraethyl orthosilicate (TEOS) and calcium is typically added in the form of calcium nitrate. The synthesis reaction proceeds in an aqueous environment; the resultant gel is dried, before stabilisation by heat treatment. These materials, being amorphous, are complex at the level of their atomic-scale structure, but their bulk properties may only be properly understood on the basis of that structural insight. Thus, a full understanding of their structure : property relationship may only be achieved through the application of a coherent suite of leading-edge experimental probes, coupled with the cogent use of advanced computer simulation methods. Using as an exemplar a calcia-silica sol-gel glass of the kind developed by Larry Hench, to whose memory this paper is dedicated, we illustrate the successful use of high-energy x-ray and neutron scattering (diffraction) methods, magic-angle spinning solid state NMR, and 1 Corresponding author: [email protected] 2 Present address: Department of Materials, Loughborough University, LE11 3TU, UK. 3 Mark Smith’s present address: Vice-Chancellor’s Office, Lancaster University, LA1 4YW, UK. 4 Richard Martin’s present address: Engineering & Applied Science, Aston University, Birmingham, B4 7ET, UK. Molecular Dynamics simulation as components to a powerful methodology for the study of amorphous materials.