Interaction of Be atoms with (111) Ir surface

It is shown that, when sputtered onto the surface of the (111) Ir face in the temperature range 1100–1250 K, beryllium atoms form a surface chemical compound of stoichiometry Ir$_3$Be with a concentration of adsorbed beryllium $N_{\mathrm{Be}}$ = 5 $\cdot$ 10$^{14}$ cm$^{-2}$, after which the newly deposited beryllium atoms dissolve metal bulk. The Ir$_3$Be surface compound itself is destroyed due to the dissolution of beryllium in the temperature range of 1250–1400 K with an activation energy increasing from 3.2 eV to 3.7 eV with decreasing Be concentration. At $T>$ 1400 K, the thermal desorption channel is switched on. The formation of the Ir$_3$Be surface compound significantly lowers the energy barrier $E$ for the dissolution of Be atoms in the bulk of iridium by $\Delta E>$ 1.7 eV.