2 Dependence of the WF with the structural relaxation

As we have mention previously, the Budapest-Vienna code does not allow us to include structural relaxation in the self-consistent procedure. For this reason, throughout this chapter when we address the case of semi-infinite fcc cobalt with a capping of an atomic monolayer of Ag, we will suppose that the lattice of the system has experimented "rigid relaxation", and we assume different values of $ r$.

In Fig. 6.4 we present the WF of a semi-infinite cobalt fcc system capped with a monolayer of Ag, for two different interfaces: (100) and (111) as a function of the rigid relaxation of the Ag lattice.

Figure 6.4: Calculated Work Function, in eV, as a function of the relaxation of the volume of the silver atom in the systems: $ Co(100)\setminus Ag_{1}$; $ Co(111)\setminus Ag_{1}$.
\includegraphics[totalheight=0.35\textheight]{WF_Co5Ag1_relax.eps}
As we can see, the work function changes with the crystal face as it has been reported previously in metals in Ref. [159], and also it is affected by the relaxation of the lattice. Nevertheless the variation of the value of the WF is lower than a $ 5\%$ of the un-relaxed one.

Rocio Yanes