Diffusion rates of 3d transition metal solutes in nickel by first-principles calculations

First-principle calculations for the diffusion of 3d transition metal (TM) solutes in nickel demonstrate the existence of a higher diffusion energy barrier for solutes with smaller atomic sizes. The calculations reveal that smaller TM atoms are, actually, among the least compressible due to the formation of incompressible solute-host directional bonds. Magnetism is shown to have a profound effect on the solute diffusion trends across the 3d TM series: the existence of a local minimum in the diffusion energy barrier is accompanied by the occurrence of a maximum in the magnetic moment. The calculated diffusion rates disprove the traditional view that the diffusion of solutes is least rapid when the size misfit with the host is the greatest.