Substitution of selenium (Se) in SrS alloys induce significant topological transitions

Purpose There are two elements, Se and S alter the electronic, structural and elastic properties of materials. This transformation is particularly evident in SrS1-xSexAlloys (x = 0.05, 0.1, 0.20, 0.3, 0.4 and 0.50), where changes in selenium concentration have led to significant changes in their behavior. Design/methodology/approach For controlling and optimizing the phase transitions in the SrS system, an effective method is employed for pressure and selenium (Se) substitution. Findings The elastic constants (C11, C12 and C44), the shear modulus (Cs), the bulk modulus (B), Kleinman internal deformation modulus (ζ), shear anisotropy coefficient (AShear) and energy band gap are investigated. In addition, we have calculated the global elastic moduli such as Lamé modulus (λ), Poisson’s ratio (v), Young’s modulus (E) and shear modulus (G). Thus, the topological invariant Z2 of the B1 phase has been calculated, providing information on the topological nature of its electronic bands and the possible presence of protected surface states, which allows for a global understanding of the behavior of the material. Originality/value This work is to add a contribution to the SrS1−xSex Alloys, which represents a challenge due to a strong interaction between macroscopic mechanical responses and structural changes at the atomic scale, both in terms of calculation and experimentally under high pressure.