First Principles Study on the Adsorption of Alkali Metal on C(100)( 2×1)
First-principles calculations based on density functional theory, using PW91 functional have been performed to study the adsorption of Alkali metal (AM) on C(100)(2×1) surface. The stable geometries, adsorption energies for all adsorption configurations have been calculated on half a monolayer and one monolayer. The preferred binding sites have been determined to be valley-bridge sites at the coverage of 0.5ML. At higher coverage of 1ML, two AM adsorbates were found to reside in pedestal site and valley-bridge site, respectively. Work function analysis showed that when AMs are adsorbed on C(100)(2×1) surface, the work function decreases linearly with increasing coverage and reaches a minimum at Θ=0.5ML. At higher coverage, the work function is increased again, which may be caused by depolarization effect of the adsorbate.
Young Won Chang, Nack J. Kim and Chong Soo Lee
J.L. Nie et al., "First Principles Study on the Adsorption of Alkali Metal on C(100)( 2×1)", Advanced Materials Research, Vols. 26-28, pp. 1341-1344, 2007