Ab Initio Modeling of Y and O Solute Atom Interaction in Small Clusters within the bcc Iron Lattice

Small yttrium and oxygen complexes in the body-centred cubic (bcc) iron matrix are modeled by performing density functional theory (DFT) calculations. The interaction between Y and O in isolated molecule, rock-salt crystal is compared with that in Y/O, Y/2O, 2Y/O clusters within the bcc iron matrix. Interaction energies and electron charge redistribution are also analyzed. Among the clusters, the most stable ones are analyzed further. It is shown that chemical bonding in YO molecule and crystal is significantly stronger than in the host matrix and the main interaction in the matrix occurs with nearby Fe atoms.