We report the formation of dimethyl sulfoxide (DMSO) molecular complexes on Au(111) enabled by native gold adatoms unusually linking the molecules via a bonding of ionic nature, yielding a mutual stabilization between molecules and adatom(s). DMSO is a widely used polar, aprotic solvent whose interaction with metal surfaces is not fully understood. By combining X-ray photoelectron spectroscopy, low temperature scanning tunneling microscopy, and density functional theory (DFT) calculations, we show that DMSO molecules form complexes made by up to four molecules arranged with adjacent oxygen terminations. DFT calculations reveal that most of the observed structures are accurately reproduced if, and only if, the negatively charged oxygen terminations are linked by one or two positively charged Au adatoms. A similar behavior was previously observed only in nonstoichiometric organic salt layers, fabricated using linkage alkali atoms and strongly electronegative molecules. These findings suggest a motif for anchoring organic adlayers of polar molecules on metal substrates and also provide nanoscale insight into the interaction of DMSO with gold.

Trapping of Charged Gold Adatoms by Dimethyl Sulfoxide on a Gold Surface

FENG, ZHIJING;VELARI, SIMONE;Cossaro, Albano;VESSELLI, ERIK;DRI, CARLO;PERESSI, MARIA;DE VITA, ALESSANDRO;COMELLI, GIOVANNI
2015

Abstract

We report the formation of dimethyl sulfoxide (DMSO) molecular complexes on Au(111) enabled by native gold adatoms unusually linking the molecules via a bonding of ionic nature, yielding a mutual stabilization between molecules and adatom(s). DMSO is a widely used polar, aprotic solvent whose interaction with metal surfaces is not fully understood. By combining X-ray photoelectron spectroscopy, low temperature scanning tunneling microscopy, and density functional theory (DFT) calculations, we show that DMSO molecules form complexes made by up to four molecules arranged with adjacent oxygen terminations. DFT calculations reveal that most of the observed structures are accurately reproduced if, and only if, the negatively charged oxygen terminations are linked by one or two positively charged Au adatoms. A similar behavior was previously observed only in nonstoichiometric organic salt layers, fabricated using linkage alkali atoms and strongly electronegative molecules. These findings suggest a motif for anchoring organic adlayers of polar molecules on metal substrates and also provide nanoscale insight into the interaction of DMSO with gold.
http://pubs.acs.org/doi/abs/10.1021/acsnano.5b02284
File in questo prodotto:
File Dimensione Formato  
Trapping of Charged Gold Adatoms by Dimethyl Sulfoxide on a Gold Surface.pdf

non disponibili

Descrizione: pdf editoriale
Tipologia: Documento in Versione Editoriale
Licenza: Digital Rights Management non definito
Dimensione 6.29 MB
Formato Adobe PDF
6.29 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
s1-ln18715141120673604-1939656818Hwf274382592IdV10727170541871514PDF_HI0001.pdf

embargo fino al 16/06/2016

Tipologia: Bozza finale post-referaggio (post-print)
Licenza: Creative commons
Dimensione 1.95 MB
Formato Adobe PDF
1.95 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11368/2846952
Citazioni
  • ???jsp.display-item.citation.pmc??? 3
  • Scopus 22
  • ???jsp.display-item.citation.isi??? 21
social impact