Site preference, magnetism and lattice vibrations of intermetallics M7−xTxB3 (M = Rh, Ru; T = Fe, Co)

The intermetallics M7B3 (M = Rh, Ru) have been studied to ascertain the effect of partial replacement of M by T (T = Fe, Co) on their phase stability and site preference. The calculated results show that Fe or Co atoms preferentially substitute M at the 2b sites. The calculated lattice parameters are in good agreement with the experimental data. We have calculated the electronic density of states and magnetic properties of M7−xTxB3 compounds. Besides, the phonon density of states of M7−xTxB3, the according specific heat, vibrational entropy and Debye temperature are calculated, and a qualitative analysis with pair potentials is also carried out.