Electronic Structures and Magnetic Properties of Transition Metal Doped CsPbI3 Perovskite Compounds by First-Principles Calculation

详细

Transition metal doped cesium lead halide (CsPbI₃) perovskite compounds were studied for application in photovoltaic solar cells. Electronic structures, chemical shifts of ²⁰⁷Pb and ¹²⁷I-NMR, vibration modes in infrared and Raman spectra of transition metals (Mn²⁺, Fe²⁺ or Cu²⁺)-doped CsPbI₃ perovskite compounds were studied by the first-principles calculation using density functional theory. The CsPb(Fe)I₃ perovskite crystals had a slight perturbation of crystal field in the coordination structure. The electron density distribution was delocalized on the 5p orbital of I atom, the 3d orbital of Fe atom and the 6p orbital of Pb atom. The first excited process was based on ligand metal charge transfer from the 5p orbital on I atom to the 3d orbital of Fe atom. The chemical shifts of ¹²⁷I-NMR were associated with the electron correlation of electron-nuclear spin interaction and nuclear quadrupole interactions based on electron field graduate. The asymmetric vibrations of Pb–I bonds stretching mode related to electron conductivity with scattering of the carrier diffusion as phonon effectiveness. The slight perturbation of the coordination structure in the CsPb(Fe)I₃ perovskite crystal will improve the photovoltaic and optical properties.