The trigonal prismatic MnO6 is a basic structural unit of Mn-based compound which has been seldom explored in theoretical and experimental studies. In this paper, the diffusion potential energy surfaces of Li+, Na+, K+, Mg2+, Al3+, and NH4+ ion in trigonal prismatic 1H-MnO2 are presented, which give an intuitionistic picture of the Jahn-Teller effect on the diffusion process. Based on the nudged elastic band method, it is found that the diffusion of ions in trigonal prismatic MnO2 is accompanied by consecutive structural distortion. The low diffusion barriers indicate trigonal prismatic MnO2 is a fast ion conductor. Band structure calculations show the semimetal characteristic of the intercalated compound, which is fit for high electrochemical performance. The details of the diffusion process are also highlighted. Our theoretical study provides an in-depth understanding and research on the fundamentals of the diffusion process in the special configuration in MnO2 and helps to develop novel high-performance electrodes.
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