Using a comprehensive structure search and high-throughput first-principles calculations of 1483 compounds, this study presents the phase diagram of Lu-H-N. The formation energy landscape of Lu-H-N was derived and utilized to assess the thermodynamic stability of compounds. Results indicate that there are no stable Lu-H-N ternary structures in this system, but metastable ternary structures, such as Lu20H2N17 (C2/m), Lu2H2N (P3-m1), were observed with small Ehull (< 100 meV/atom). Moreover, applying hydrostatic pressure up to 10 GPa causes the energy convex hull of the Lu-H-N to shift its shape and stabilizes binary phases such as LuN9 and Lu10H21. Additionally, interstitial empty sites in LuH2 were noted, which may explain the formation of Lu10H21 and LuH3-xNy. To provide a basis for comparison, X-ray diffraction patterns and electronic structures of some compounds are also presented.
@article{arxiv.2303.11683,
title = {Lu-H-N phase diagram from first-principles calculations},
author = {Fankai Xie and Tenglong Lu and Ze Yu and Yaxian Wang and Zongguo Wang and Sheng Meng and Miao Liu},
journal= {arXiv preprint arXiv:2303.11683},
year = {2023}
}