Perovskites have garnered significant attention in recent years. However, the presence of La atoms at the $B$-site in $ABX_3$ structures has not yet been observed. Under high pressure, perovskites exhibit unexpected phase transitions. In this study, we report the discovery of SbLaO$_3$ under ambient pressure, with a space group of $R3m$. Mechanical property calculations indicate that it is a brittle material, and it possesses a band gap of 4.0266 eV, classifying it as an insulator. We also investigate the phase at 300 GPa, where the space group shifts to $P2_{1}/m$. Additionally, the $P2_{1}/m$ phase of LaInO$_3$ under 300 GPa is explored. Ab initio molecular dynamics calculations reveal that the melting point of SbLaO$_3$ is exceptionally high. The inclusion of Sb alters the electronic structure compared with LaInO$_3$, and the Vickers hardness ($H_{\rm v}$) is estimated to reach 20.97 GPa. This research provides insights into the phase transitions of perovskites under high pressure.

The IV-VI semiconducting chalcogenides are a large material family with distinct physical behavior. Here, we systematically investigate the effect of pressure on the electronic and crystal structures of PbSe and PbTe by combining high-pressure electrical transport and synchrotron x-ray diffraction (XRD) measurements. The resistivity of PbSe and PbTe changes dramatically under high pressure and a non-monotonic evolution of $\rho (T)$ is observed. Both PbSe and PbTe are found to undergo semiconductor-metal transition upon compression and show superconductivity under higher pressure. The structural evolutions from the Fm$\bar{3}m$ to Pnma phase and then to the Pm$\bar{3}m$ phase in PbSe are verified by the x-ray diffraction. The present findings reveal the internal correlation between the structural evolution and the physical properties in lead chalcogenides.

High-pressure studies of two-dimensional materials have revealed numerous novel properties and physical mechanisms behind them. As a typical material of transition metal dichalcogenides (TMDs), ZrSe$_{2}$ exhibits high carrier mobility, rich electronic states regulated by doping, and high potential in applications at ambient pressure. However, the properties of ZrSe$_{2}$ under pressure are still not clear, especially for the structural and electrical properties. Here, we report the investigation of ZrSe$_{2}$ under pressure up to 66.5 GPa by in-situ x-ray diffraction, Raman, electrical transport measurements, and first-principles calculations. Two structural phase transitions occur in ZrSe$_{2}$ at 8.3 GPa and 31.5 GPa, from $P$-3$m$1 symmetry to $P$2$_{1}$/$m$ symmetry, and finally transformed into a non-layer $I$4/mmm symmetry structure. Pressure-induced metallic transition is observed at around 19.4 GPa in phase II which aligns well with the results of the calculation. Our work will help to improve the understanding of the evolution of the structure and electrical transport properties of two-dimensional materials.

Recently, many encouraging experimental advances have been achieved in ternary hydrides superconductors under high pressure. However, the extreme pressure required is indeed a challenge for practical application, which promotes a further exploration for high temperature ($T_{\rm c}$) superconductors at relatively low pressure. Herein, we performed a systematic theoretical investigation on a series of ternary hydrides with stoichiometry $AX_2$H$_8$, which is constructed by interacting molecular $X$H$_4$ ($X=$ B, C, and N) into the fcc metal $A$ lattice under low pressure of 0-150 GPa. We uncovered five compounds which are dynamically stable below 100 GPa, e.g., AcB$_2$H$_8$ (25 GPa), LaB$_2$H$_8$ (40 GPa), RbC$_2$H$_8$ (40 GPa), CsC$_2$H$_8$ (60 GPa), and SrC$_2$H$_8$ (65 GPa). Among them, AcB$_2$H$_8$, which is energetically stable above 2.5 GPa, exhibits the highest $T_{\rm c}$ of 32 K at 25 GPa. The superconductivity originates mainly from the coupling between the electron of Ac atoms and the associated low-frequency phonons, distinct from the previous typical hydrides with H-derived superconductivity. Our results shed light on the future exploration of superconductivity among ternary compounds at low pressure.