title: Metal to insulator transition in films of molecularly linked gold nanoparticles.
abstract: We report a metal to insulator transition (MIT) in disordered films of molecularly linked gold nanoparticles (NPs). As the number of carbons (n) of alkanedithiol linker molecules (C(n)S2) is varied, resistance (R) at low temperature (T = 2 K) and at 200 K, as well as trends in R vs T data at intermediate temperatures, all point to an MIT occurring at n = 5. We describe these results in a context of a Mott-Hubbard MIT. We find that all insulating samples (n > or = 5) exhibit a universal scaling behavior R approximately exp[(T0/T)nu] with nu = 0.65, and all metallic samples (n < or = 5) exhibit weaker R-T dependencies than bulk gold. We discuss these observations in terms of competitive thermally activated processes and strong, T-independent elastic scattering, respectively.
authors.affiliation: Department of Chemistry, University of Toronto, Toronto, Ontario, M5S 3H6, Canada.
authors.forename: Amir
authors.initials: A
authors.lastname: Zabet-Khosousi
authors.forename: Paul-Emile
authors.initials: PE
authors.lastname: Trudeau
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Suganuma
authors.forename: Al-Amin
authors.initials: AA
authors.lastname: Dhirani
authors.forename: Bryan
authors.initials: B
authors.lastname: Statt