Structural investigation of 1,1'-biphenyl-4-thiol self-assembled monolayers on Au(111) by scanning tunneling microscopy and low-energy electron diffraction.
Langmuir
; 28(39): 13905-11, 2012 Oct 02.
Article
em En
| MEDLINE
| ID: mdl-22953697
ABSTRACT
Self-assembled monolayers (SAMs) of 1,1'-biphenyl-4-thiol (H-(C(6)H(4))(2)-SH) on Au(111) were prepared from solution or via vapor deposition in ultrahigh vacuum and characterized by scanning tunneling microscopy (STM), low-energy electron diffraction (LEED), and X-ray photoelectron spectroscopy (XPS). In contrast to the typically observed for densely packed alkane-thiol SAMs on Au(111) (â3 × â3)R30° structure, the densely packed aromatic biphenylthiol SAMs prepared by both methods exhibit an unusual hexagonal (2 × 2) structure. Upon annealing at 100 °C, this structure evolves into the (2 × 7â3) structure resulting in the formation of highly ordered pinstripes oriented along the [1 -1 0] directions. Lower density SAMs, prepared by vapor deposition in vacuum, show mixed structures comprising the hexagonal (2 × 2) structure and two rectangular arrangements with the unit cells of (3â3 × 9) and (2â3 × 8). An extinction of the (3â3 × 9) structure in the favor of the (2â3 × 8) structure is observed upon annealing at temperatures of ~100 °C.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Compostos de Sulfidrila
/
Compostos de Bifenilo
/
Elétrons
/
Ouro
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article