Theoretical studies of high-Tc Fe-superconductors based on BaFe2As2 in presence of dopants Rh and Pd

Abstract

One of the recent discoveries is the superconductivity in the Fe- based materials with anti-ferromagnetic state at ambient temperature. The pure material BaFe2As2 is a semi-metal and has not superconductivity. The transition to the superconductivity state appeared in presence of different dopants. In this report we present the results of calculations using the embedded cluster method at the RO-MP2 electron correlation level and two suites of programs MOLPRO 2019 and Gaussian 16. The cluster Ba4Fe5As8 in presence of Rh and Pd as dopants was used. The NBO population analysis showed two main features: the independence of charge density transfer from the spin density transfer and, the presence of orbitals with electron density but without spin density. The observed properties correspond to the RVB mechanism for the superconductivity proposed by Anderson for cuprates. This confirmed the conclusions made in our publications for the same material doped by Co and Ni.