Study of electronic properties of Al3Ti, AlTi and AlTi3 intermetallic compounds using DFT-FPLAPW

Abstract

The electronic properties of Al-Ti intermetallics are receiving great attention in the specialized literature because these alloys present excellent mechanical performance at high temperatures. This consideration prompted our DFT-LDA and DFT-GGA ab initio study on electronic band structures, density of states, contour plots, Fermi Surface, Bulk modulus, and cohesive energy of intermetallics Al_{3}Ti, AlTi, and AlTi_{3} using the FP-LAPW method. The band structure confirms their electrical conductivity, AlTi_{3} featuring a highly localized band associated to Ti 3d electrons around the Fermi level, not observed in the others. The DOS around the Fermi level is dominated by interactions between Al 3p and Ti 3d orbitals, whereas Al 3s and Ti 3d orbital interactions prevail in the regions of low and high energies, respectively. The density pseudogap in AlTi_{3} is located very close to the Fermi Level, granting a greater structural stability to this system. The Fermi Surface of these intermetallics, for which the authors found no previous reference in the literature, is reported. The difference in density distribution for the LDA and GGA methods is reflected in the contour plots. The Bulk modulus and cohesive energy values reported are in agreement with those reported in the literature.