| Abstrakt: |
Recently, a large number of theoretical and experimental studies have reported the emergence of a new sp³ clathrate XB3C3, where X represents different metal doping elements. The potential high-temperature superconducting materials have been discovered. New-typical cage material with both strong covalent and superconducting properties has important scientific research significance. In recent years, Ac discovered as the first element of the actinide series, AcH10 has a superconducting transition temperature (Tc) of 251 K, making it a potential room temperature superconductor. Therefore, in this article, first principles density functional theory is used to explore the crystal structure, lattice dynamics, electronic properties, and superconducting properties of AcB3C3, AcB2C4, and AcB4C4 doped with Ac elements based on the cage structures of XB3C3, XB2C4, and XB4C2. Research has found that AcB2C4 is difficult to synthesize within the 0-200 GPa range, and AcB3C3 exhibits an indirect bandgap semiconductor with a bandgap width of approximately 1.154 eV at atmospheric pressure. Based on the mechanical stability criterion, it can be inferred that AcB3C3 and AcB4C2 are brittle materials with high hardness and stiffness that are elastically stable. At the same time, AcB4C2 exhibits superconducting properties at ambient pressure, with Tc reaching 1.565 K. It has been observed that as pressure increases, the Tc value exhibits a trend of initially decreasing and then increasing. The superconducting mechanism is mainly influenced by intermediate-frequencies phonons, which then shift to the combination of low-frequencies and intermediate-frequencies phonons. This study provides guidance for the experimental synthesis of cage type compound superconducting materials and provides new ideas for exploring superconducting materials with high superconducting transition temperature. [ABSTRACT FROM AUTHOR] |
