Computational investigation on the fn→fn−1d effect on the electronic transitions of clinoptilolite

Abstract Understanding how f-shell electron adsorption affects the clinoptilolite is important for buffer-backfill material. However, there have been only a very limited number of reports of the quantitative simulation of the effects of fn → fn − 1d transitions on the phase transition. In this study, the density functional theory (DFT) and two-dimensional correlation analysis (2D-CA) techniques were used to calculate the origins of the structural and electronic transitions of f-clinoptilolite. The results showed that the fn → fn − 1d transitions are attributed to the sp3d orbital hybridisation in the silicon–oxygen tetrahedron, consistent with the orbital fluctuation result. This study offers a new perspective on the development of the oxygen activation mechanism.