Quantum size effect in Pb(100) films: Role of symmetry and implications for film growth
نویسندگان
چکیده
We show from density-functional calculations that Pb 100 thin films exhibit quantum size effect with a bilayer periodicity in film energies, film relaxations, and work functions, which originate from different symmetry of the stacking geometry of odd and even layer films. This symmetry-driven quantum size effect on the film energy could allow for growth of “magically” thick even-layer Pb 100 films on an appropriate substrate. Furthermore, it is found that the quantum well states in a simple metal film can be classified into -bonded and -bonded states, which quantize independently.
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