Perovskite material refers to a family of compounds with \({\text{ABX}}_{3}\) structure, whose structure is an octahedron composed of a large number of different elements. It is precisely because of this special structural property that it has various optical and electrical properties, which are determined by the polaron effect, that it is crucial to study the polaron effect. To investigate the photoelectric effect of polaron, the key is to solve the ground state level of polaron. Therefore, this paper studies the relationship between the polaron’s ground state energy, polaron radius, vector, and pseudopotential, and obtains the expression of polaron ground state level with the unitary transformation and the Pekar variational method. For different perovskite materials, we observe the change in the energy of the ground state. Find the same material, while the polaron radius is a fixed value, and the ground state energy increases gradually with the bit vector and the pseudopotential.
