Growth and thermal stability of Fe and Ni adsorption layers on the (1 1 1) Ta crystal face

It has been found that after heating up to T>800 K iron forms a surface solution with tantalum that exhibits a face centred cubic structure. The lattice constant of this structure depends on the annealing temperature and initial coverage. For the adsorption of Ni, the Ni(1 1 1) structure with two different orientations has been observed after heating up to T>900 K. The layer oriented [1 1 0]Ni∥[1 1 0]Ta has been formed at lower coverages θ<5 ML, while the layer oriented [1 1 0]Ni∥[2 1 1]Ta has appeared for thicker layers. The values of the lattice constant for these layers have been identical to that of a Ni single crystal.