Scanning the latent phases and superconductivity in the Th-B system at high pressure

In this work, we carried out systematic calculations on the Th-B binary compounds at high pressure from evolutionary algorithm and density functional theory. We discovered two possible pressure-stabilized phases Th2B and Th2B5 in the Th-B binary system. Additionally, we found two thermodynamically metastable phases ThB5 and Th2B13 with unusual geometric structures, which exhibit considerable superconducting transition temperatures 22 K and 33 K at high pressures, respectively. Furthermore, the discovery of Th2B13 with a dumbbell-shaped truncated octahedral B atom cage structure, and ThB5 with a B20-cage structure provides insights from the perspective of crystal geometry for the search of high temperature superconductors.