Spatially and rotationally oriented adsorption of molecular adsorbates on Ag(111) investigated using cryogenic scanning tunneling microscopy

TitleSpatially and rotationally oriented adsorption of molecular adsorbates on Ag(111) investigated using cryogenic scanning tunneling microscopy
Publication TypeJournal Article
Year of Publication1996
AuthorsChen, X, Frank, ER, Hamers, RJ
JournalJournal of Vacuum Science & Technology B
Volume14
Pagination1136-1140
Date PublishedMar-Apr
Type of ArticleProceedings Paper
ISBN Number1071-1023
Accession NumberISI:A1996UH89000111
Keywordsthiophene
Abstract

The molecular adsorption of thiophene and 2,5-dimethylthiophene on Ag(111) surfaces is studied using a cryogenic scanning tunneling microscope (STM) operating at 120 K. Thiophene molecules are observed to adsorb preferentially at step edges, occupying the upper step edge at lowest coverage, and additionally occupying the lower step edge at higher coverage. The adsorption site and rotational orientation of 2.5-dimethylthiophene were identified. Molecules at step edges art: observed to cluster, indicating an attractive interaction between molecules at step edges. As the coverage increases, a phase transition corresponding to a transition from a planar to a tilted geometry is observed. (C) 1996 American Vacuum Society.

URL<Go to ISI>://A1996UH89000111