1. The ion-irradiation tolerance of the pyrochlore to fluorite Ho(x)Yb(2-x)TiO5 and Er2TiO5 compounds: A TEM comparative study using both in-situ and bulk ex-situ irradiation approaches.
- Author
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Aughterson, Robert D., Lumpkin, Gregory R., Smith, Katherine L., Reyes, Massey de los, Davis, Joel, Avdeev, Maxim, Ridgway, Mark C., and Cairney, Julie M.
- Subjects
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PYROCHLORE , *CALCIUM fluoride , *HOLMIUM compounds , *TITANIUM dioxide , *ERBIUM compounds , *TRANSMISSION electron microscopy - Abstract
We refine the crystal structures of a systematic series of compounds with the general composition Ho (x) Yb (2-x) TiO 5 (x = 2, 1.6, 1.2, 1, 0.8, 0.4, 0) and Er 2 TiO 5 and find a transition from defect-pyrochlore to defect-fluorite structure with increasing ytterbium content, decreasing lanthanide radius. Short-range structure modulations consisting of pyrochlore-like nano-domains are systematically characterised using transmission electron microscopy. We test the Kr 2+ 1 MeV ion-irradiation response of Ho 2 TiO 5 , HoYbTiO 5 , Yb 2 TiO 5 , and Er 2 TiO 5 , via the crystalline to amorphous transition observed by using the in-situ TEM approach. The critical dose of amorphisation, D c , was measured at various temperatures and used to calculate the critical temperature for maintaining crystallinity, T c . A trend of lower T c values with decreasing lanthanide radius is found. We describe a new approach for determining T c values using cross-sectional TEM analysis of ex-situ bulk irradiated, 1 MeV Se + , samples; Ho 2 TiO 5 , HoYbTiO 5 and Yb 2 TiO 5 . The results of D c and T c values using the two approaches vary; however the trends across the sample system remain the same. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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