Confirmation of a de novo structure prediction for an atomically precise monolayer-coated silver nanoparticle

Brian E Conn; Aydar Atnagulov; Bokwon Yoon; Robert N Barnett; Uzi Landman; Terry P Bigioni

doi:10.1126/sciadv.1601609

Confirmation of a de novo structure prediction for an atomically precise monolayer-coated silver nanoparticle

Sci Adv. 2016 Nov 25;2(11):e1601609. doi: 10.1126/sciadv.1601609. eCollection 2016 Nov.

Authors

Brian E Conn¹, Aydar Atnagulov¹, Bokwon Yoon², Robert N Barnett³, Uzi Landman³, Terry P Bigioni⁴

Affiliations

¹ Department of Chemistry, University of Toledo, Toledo, OH 43606, USA.
² School of Solar and Advanced Renewable Energy, University of Toledo, Toledo, OH 43606, USA.
³ School of Physics, Georgia Institute of Technology, Atlanta, GA 30332-0430, USA.
⁴ Department of Chemistry, University of Toledo, Toledo, OH 43606, USA.; School of Solar and Advanced Renewable Energy, University of Toledo, Toledo, OH 43606, USA.

Abstract

Fathoming the principles underpinning the structures of monolayer-coated molecular metal nanoparticles remains an enduring challenge. Notwithstanding recent x-ray determinations, coveted veritable de novo structural predictions are scarce. Building on recent syntheses and de novo structure predictions of M₃Au _x Ag_17-x (TBBT)₁₂, where M is a countercation, x = 0 or 1, and TBBT is 4-tert-butylbenzenethiol, we report an x-ray-determined structure that authenticates an a priori prediction and, in conjunction with first-principles theoretical analysis, lends force to the underlying forecasting methodology. The predicted and verified Ag(SR)₃ monomer, together with the recently discovered Ag₂(SR)₅ dimer and Ag₃(SR)₆ trimer, establishes a family of unique mount motifs for silver thiolate nanoparticles, expanding knowledge beyond the earlier-known Au-S staples in thiol-capped gold nanoclusters. These findings demonstrate key principles underlying ligand-shell anchoring to the metal core, as well as unique T-like benzene dimer and cyclic benzene trimer ligand bundling configurations, opening vistas for rational design of metal and alloy nanoparticles.

Keywords: Atomically precise ligand-protected nanoclusters; capping ligand mounts; de novo structure prediction; electronic shell strcture; first-principles DFT calculations; interligand conformations; ligand bundling; optical absorption measurements and TDDFT calculations; silver nanoclusters; x-ray structure determination.