title: Single-molecule SERS detection of C60.
abstract: Single-molecule Surface-Enhanced Raman Scattering (SERS) detection of buckminsterfullerene (C(60)) is achieved by using different isotopologues of the molecule with a distribution around an average isotopic substitution ((12)C → (13)C) of ~30%. The distribution of different isotopologues creates a broad (~20 cm(-1)) average SERS signal within which single-molecule SERS spectra of individual isotopic realizations of the molecule can be distinguished. The SERS enhancement factors for SM-SERS C(60) events are typically in the range of ~10(8), suggesting a limitation imposed by either photobleaching or surface interactions with the (Ag) metallic colloids to reach the highest SERS hot-spots (which can typically have larger maximum enhancements). SM-SERS signals of isotopically substituted C(60) also show broader peaks (FWHM ≈ 4 cm(-1)) than equivalent signals in natural C(60). The latter feature suggests a contribution to the homogeneous broadening coming from isotopic disorder in the molecule; a feature that can only be observed with the ability to detect single-molecule spectra.
authors.affiliation: The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Chemical and Physical Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand.
authors.forename: Camille G
authors.initials: CG
authors.lastname: Artur
authors.forename: Rowan
authors.initials: R
authors.lastname: Miller
authors.forename: Matthias
authors.initials: M
authors.lastname: Meyer
authors.forename: Eric C
authors.initials: EC
authors.lastname: Le Ru
authors.forename: Pablo G
authors.initials: PG
authors.lastname: Etchegoin