title: Size-dependent commensurability and its possible role in determining the frictional behavior of adsorbed systems.
abstract: Recent nanofriction experiments of xenon on graphene revealed that the slip onset can be induced by increasing the adsorbate coverage above a critical value, which depends on temperature. Moreover, the xenon slippage on gold is much higher than on graphene in spite of the same physical nature of the interactions. To shed light on these intriguing results we have performed molecular dynamics simulations relying on ab initio derived potentials. By monitoring the interfacial structure factor as a function of coverage and temperature, we show that the key mechanism to interpret the observed frictional phenomena is the size-dependence of the island commensurability. The latter quantity is deeply affected also by the lattice misfit, which explains the different frictional behavior of Xe on graphene and gold.
authors.affiliation: Dipartimento di Scienze Fisiche, Informatiche e Matematiche, Università di Modena e Reggio Emilia, Via Campi 213/A, I-41125 Modena, Italy.
authors.forename: Paolo
authors.identifier: http://orcid.org/0000-0002-0419-723X
authors.initials: P
authors.lastname: Restuccia
authors.affiliation: Dipartimento di Scienze Fisiche, Informatiche e Matematiche, Università di Modena e Reggio Emilia, Via Campi 213/A, I-41125 Modena, Italy.
authors.forename: Mauro
authors.identifier: http://orcid.org/0000-0001-6754-9055
authors.initials: M
authors.lastname: Ferrario
authors.affiliation: Dipartimento di Fisica e Astronomia, Università di Padova, via Marzolo 8, I-35131, Padova, Italy.
authors.forename: Pier Luigi
authors.initials: PL
authors.lastname: Sivestrelli
authors.affiliation: Dipartimento di Fisica e Astronomia, Università di Padova, via Marzolo 8, I-35131, Padova, Italy.
authors.forename: Giampaolo
authors.initials: G
authors.lastname: Mistura
authors.affiliation: Dipartimento di Scienze Fisiche, Informatiche e Matematiche, Università di Modena e Reggio Emilia, Via Campi 213/A, I-41125 Modena, Italy and CNR-Institute of Nanoscience, S3 Center, Via Campi 213/A, I-41125 Modena, Italy. mariaclelia.righi@unimore.it.
authors.forename: Maria Clelia
authors.initials: MC
authors.lastname: Righi