ISIS Neutron and Muon Source Data Journal

The structure and thermal expansion of Geikielite (MgTiO?) at high temperature

Abstract: Geikielite (MgTiO3) is a rhombohedral ilmenite-structured mineral, characterised by alternating layers of octahedrally coordinated Mg and Ti cations. The structural properties and thermal characteristics of MgTiO3, and of the isostructural mineral ilmenite (FeTiO3), are of importance for understanding early lunar geology, in particular for the analysis of buoyancy forces that cause material to sink and rise in the lunar mantle, leading to a possible lunar mantle overturn and a deep melt layer. In addition, MgTiO3 is of interest industrially as a dielectric material for use in microwave and other electronic devices. We have measured the thermal expansion of geikielite at UCL from 40 K to 1473 K by X-ray powder diffraction and we have found an anomalous increase in the thermal expansion coefficient above about 1100 K. We wish to investigate the structural origin of this effect by neutron powder diffraction and also to extend our thermal expansion measurements to higher (and more geologically relevant) temperatures than those that we can achieve at UCL.

Principal Investigator: Professor Ian Wood
Experimenter: Mr Ry Affleck
Local Contact: Dr Ronald Smith
Experimenter: Professor John Brodholt
Experimenter: Professor Andrew Thomson
Experimenter: Professor Lidunka Vocadlo

DOI: 10.5286/ISIS.E.RB2610173

ISIS Experiment Number: RB2610173

Publisher: STFC ISIS Neutron and Muon Source

Data format: RAW/Nexus
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Data Citation

The recommended format for citing this dataset in a research publication is as:
[author], [date], [title], [publisher], [doi]

For Example:
Professor Ian Wood et al; (2026): The structure and thermal expansion of Geikielite (MgTiO?) at high temperature , STFC ISIS Neutron and Muon Source, https://doi.org/10.5286/ISIS.E.RB2610173

Data is released under the CC-BY-4.0 license.