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Adsorption, interaction, and diffusion of adatoms on surfaces control growth and relaxation of epitaxial nanostructures and nanofilms. Previous reports of key diffusion barriers for Pb diffusion on low-index Pb surfaces are limited in scope and accuracy. Thus, we apply density functional theory (DFT) to calculate the adsorption and diffusion energetics for a Pb adatom on Pb(111), Pb(100), and Pb(110) nanofilms with different thicknesses. We find that these quantities exhibit damped oscillatory variation with increasing film thickness. For Pb(111) films, energetics along the minimum energy path for Pb adatom diffusion between adjacent fcc and hcp sites varies significantly with film thickness, its form differing from other metal-onmetal(111) systems. For Pb(111) and Pb(100) nanofilms, diffusion barriers obtained for both adatom hopping and exchange mechanism differ significantly from previous DFT results. Hopping is favored over exchange for Pb(111), and the opposite applies for Pb(100). For Pb(110) nanofilms, Pb adatom hopping over an in-channel bridge is most facile, then in-channel exchange, then cross-channel exchange, with crosschannel hopping least favorable. We also assess lateral Pb adatom interactions, and characterize island nucleation during deposition on Pb(111). Disciplines Condensed Matter Physics | Materials Science and Engineering | Physics Comments This article is published as Li, Wei, Li Huang, Raj Ganesh S. Pala, Guang-Hong Lu, Feng Liu, James W. Evans, and Yong Han. "Thickness-dependent energetics for Pb adatoms on low-index Pb nanofilm surfaces: Firstprinciples calculations." Physical Review B 96, no. 20 (2017): 205409. DOI: 10.1103/PhysRevB.96.205409. Posted with permission. Authors Wei Li, Li Huang, Raj Ganesh S. Pala, Guang-Hong Lu, Feng Liu, James W. Evans, and Yong Han This article is available at Iowa State University Digital Repository: https://lib.dr.iastate.edu/physastro_pubs/459 PHYSICAL REVIEW B 96, 205409 (2017) Thickness-dependent energetics for Pb adatoms on low-index Pb nanofilm surfaces: First-principles calculations Wei Li,1 Li Huang,1,* Raj Ganesh S. Pala,2,3 Guang-Hong Lu,4,5 Feng Liu,6 James W. Evans,7,8 and Yong Han7,8,† 1Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong 518055, People’s Republic of China 2Department of Chemical Engineering, Indian Institute of Technology Kanpur, UP, 208016, India 3Material Science Programme, Indian Institute of Technology Kanpur, UP, 208016, India 4Department of Physics, Beihang University, Beijing 100191, China 5Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beihang University, Beijing 100191, China 6Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA 7Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA 8Ames Laboratory–U.S. Department of Energy, Iowa State University, Ames, Iowa 50011, USA (Received 11 June 2017; revised manuscript received 24 September 2017; published 6 November 2017) Adsorption, interaction, and diffusion of adatoms on surfaces control growth and relaxation of epitaxial nanostructures and nanofilms. Previous reports of key diffusion barriers for Pb diffusion on low-index Pb surfaces are limited in scope and accuracy. Thus, we apply density functional theory (DFT) to calculate the adsorption and diffusion energetics for a Pb adatom on Pb(111), Pb(100), and Pb(110) nanofilms with different thicknesses. We find that these quantities exhibit damped oscillatory variation with increasing film thickness. For Pb(111) films, energetics along the minimum energy path for Pb adatom diffusion between adjacent fcc and hcp sites varies significantly with film thickness, its form differing from other metal-on-metal(111) systems. For Pb(111) and Pb(100) nanofilms, diffusion barriers obtained for both adatom hopping and exchange mechanism differ significantly from previous DFT results. Hopping is favored over exchange for Pb(111), and the opposite applies for Pb(100). For Pb(110) nanofilms, Pb adatom hopping over an in-channel bridge is most facile, then in-channel exchange, then cross-channel exchange, with cross-channel hopping least favorable. We also assess lateral Pb adatom interactions, and characterize island nucleation during deposition on Pb(111). DOI: 10.1103/PhysRevB.96.205409