Percolation of hydrogen atoms adsorbed on Cu(100) surfaces: DFT, Monte Carlo and finite size scaling techniques.

ELIZABETH DEL VALLE GÓMEZ; LUCÍA B. AVALLE; M. CECILIA GIMÉNEZ

Buenos Aires

Congreso; Statphys 27; 2019

UBA

The percolation of hydrogen adsorption on Cu(100) surfaces was studied.In order to obtain realistic approximations, DFT calculations were perfomed to calculate adsorption energies of a hydrogen atom in different environments, according to the number of first neighbours present at each adsorption site. This information was employed in Monte Carlo simulations and the percolation threshold was calculated for different temperatures. A phase diagram which separates percolating and non percolating regions was obtained. Critical exponents were also calculated in order to study the universality of the system. At temperatures below 200K, a particular and interesting behavior was observed, which is evidenced by the results obtained for the isotherms, phase diagram and critical exponents. At higher temperatures, the behavior observed for percolating properties is that expectedfor repulsive interactions between neighboring adsorbed hydrogen atoms.