DIFFERENTIATING FUNCTIONAL-GROUPS WITH THE SCANNING TUNNELING MICROSCOPE

Venkataraman, B; Flynn, GW; Wilbur, JL; Folkers, JP; Whitesides, GM

HERO ID

1734002

Reference Type

Journal Article

Year

1995

HERO ID 1734002
In Press No
Year 1995
Title DIFFERENTIATING FUNCTIONAL-GROUPS WITH THE SCANNING TUNNELING MICROSCOPE
Authors Venkataraman, B; Flynn, GW; Wilbur, JL; Folkers, JP; Whitesides, GM
Journal Journal of Physical Chemistry
Volume 99
Issue 21
Page Numbers 8684-8689
Abstract Scanning tunneling microscopy (STM) images of 1-docosanol, 1-docosanethiol, didocosyl disulfide, and 1-chlorooctadecane on graphite are compared. The images of the 1-docosanethiol and didocosyl disulfide show bright spots which are attributed to the positions of the S-H and S-S functional groups. The STM images of the 1-docosanol and 1- chlorooctadecane do not show such bright spots. The fact that both the S-H and S-S groups appear bright in the STM images indicates that the presence of an S atom on graphite results in a higher tunneling current when the tip scans over it compared to the tunneling current over a C, O, or Cl atom. The different behavior of the S atoms compared to the O, C, and Cl atoms is discussed in terms of the interactions between these atoms and the underlying graphite substrate. The persistent brightness of S atoms in the images of molecular adsorbates suggests that sulfur may serve as a useful ''chromophore'' for molecules imaged by STM.
Doi 10.1021/j100021a038
Wosid WOS:A1995RA14700038
Is Certified Translation No
Dupe Override No
Comments Source: Web of Science WOS:A1995RA14700038 Journal:JOURNAL OF PHYSICAL CHEMISTRY 0022-3654
Is Public Yes