Research objectives and content
The primary scientific objective of the project is to produce a fully quantitative description of the local structural state of the binary silicate solid solution diopside (CaMgSi2O6) - Ca-Tschermak (CaAl2SiO6). In a new approach, a combination of the most up-to-date experimental techniques and computational simulation methods will be used to determine the structural and energetical change associated with the mixing process on an atomistic scale.The experimental techniques to be used are: 1) 29Si MAS NMR spectroscopy to characterise the degree of order of the samples on a local basis and 2) hard mode infrared spectroscopy (HMIR) for probing local structural distortions.The computational techniques to be used are 1) lattice energy calculations for modelling the energetical changes resulting from the mixing process and interaction energies between cations on neighbouring structural sites and 2)Monte Carlo models for the simulation of configura- tional effects such as the configurational entropy of mixing. The results of this study will be used to develop a concise picture of the dominant factors governing the mixing process of solid solutions on an atomistic scale.
Training content (objective, benefit and expected impact)
During the experimental part of the project the applicant will be trained in the hands-on application of the MAS NMR spectroscopy and the new method of HMIR spectroscopy. The theoretical part will train her in the backround and use of computational methods applied to solids. The combination of experimen- -tal and computational skills acquired during the course of the project represent a particularly valuable and timely training for future research in either academia or industry.
Links with industry / industrial relevance (22)
The host institution has direct contact to various UK and EU companies which are actively involved in research on mixing properties of silicate solid solutions such as Schlumberger, Pilkington and Redland.