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arXiv · 2204.06703

First-Principles investigation of the First-order Phase Transition in Kagome Na$_2$Ti$_3$Cl$_8$

Shuang Liu·Zhi-Bo Yin·Meng-Qiu Long·Yun-Peng Wang
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Abstract

The antiferromagnetic kagome material Na2Ti3Cl8 exhibits a first-order phase transition; the low-temperature phase is characterized by the trimerizations of Ti ions. In this work, we carry out first-principles calculations on the crystal and electronic structure of Na$_2$Ti$_3$Cl$_8$ at the high- and low-temperature phases. The crystal structures, including the lattice constant and the trimerization of Ti ions, are well reproduced by taking account a small Hubbard correction of 1 eV. The calculated total energy landscape reveals a first-order phase transition with the total energy barrier of 80 meV per formula unit. Analysis of the electronic structure indicates a direct metal bonding among Ti in the trimierized low-temperature phase.

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Shuang Liu, Zhi-Bo Yin, Meng-Qiu Long, Yun-Peng Wang. 2022-04-14. First-Principles investigation of the First-order Phase Transition in Kagome Na$_2$Ti$_3$Cl$_8$. https://arxiv.org/abs/2204.06703

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