title: Mechanism for Si-Si Bond Rupture in Single Molecule Junctions.
abstract: The stability of chemical bonds can be studied experimentally by rupturing single molecule junctions under applied voltage. Here, we compare voltage-induced bond rupture in two Si-Si backbones: one has no alternate conductive pathway whereas the other contains an additional naphthyl pathway in parallel to the Si-Si bond. We show that in contrast to the first system, the second can conduct through the naphthyl group when the Si-Si bond is ruptured using an applied voltage. We investigate this voltage induced Si-Si bond rupture by ab initio density functional theory calculations and molecular dynamics simulations that ultimately demonstrate that the excitation of molecular vibrational modes by tunneling electrons leads to homolytic Si-Si bond rupture.
authors.affiliation: Department of Applied Physics and Applied Mathematics, Columbia University , New York, New York 10027, United States.
authors.forename: Haixing
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Chemistry, Columbia University , New York, New York 10027, United States.
authors.forename: Nathaniel T
authors.initials: NT
authors.lastname: Kim
authors.affiliation: Department of Chemistry, Columbia University , New York, New York 10027, United States.
authors.forename: Timothy A
authors.initials: TA
authors.lastname: Su
authors.affiliation: Department of Chemistry, Columbia University , New York, New York 10027, United States.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Steigerwald
authors.affiliation: Department of Chemistry, Columbia University , New York, New York 10027, United States.
authors.forename: Colin
authors.initials: C
authors.lastname: Nuckolls
authors.affiliation: Center for Nanoscale Materials, Argonne National Laboratory , Argonne, Illinois 60439, United States.
authors.forename: Pierre
authors.initials: P
authors.lastname: Darancet
authors.affiliation: Department of Chemistry, Columbia University , New York, New York 10027, United States.
authors.forename: James L
authors.initials: JL
authors.lastname: Leighton
authors.affiliation: Department of Applied Physics and Applied Mathematics, Columbia University , New York, New York 10027, United States.|Department of Chemistry, Columbia University , New York, New York 10027, United States.
authors.forename: Latha
authors.initials: L
authors.lastname: Venkataraman