Electronic structure study of the dependence of the pseudogap on the icosahedral cluster size and glue atoms

Electronic structures of crystalline All2Mn, Al42Mn13 and Al54Mn13 are calculated by the tight-binding linear muffin-tin orbital method with the atomic sphere approximation in the local density functional framework. The density of states for Al12, Mn shows a pseudogap at the Fermi level, whereas it is very much reduced and away from Fermi level in the case of the Al42Mnl3 crystal. The evolution of a pseudogap near the Fermi level is observed in A154Mn13 with the addition of glue atoms. Our results show that the pseudogap does not depend upon the icosahedral cluster size, for the Al-Mn system; however, it is sensitive to the presence of the glue atoms