Determination of Adsorbate Structures from 1,4-Phenylene Diisocyanide on Gold.
The structure of the 1-D oligomer chains that form on a Au(111) surface following adsorption of 1,4-phenylene diisocyanide (PDI) is explored using reflection-absorption infrared spectroscopy and scanning tunneling microscopy (STM). The experimental work is complemented by first-principles density functional theory calculations, which indicate that the previously proposed gold-PDI oligomer chains in which the PDI molecule bridged gold adatoms are thermodynamically stable. In addition, the calculated vibrational modes for this structure are in excellent agreement with the experimental infrared data. The linkage of the PDI units by gold adatoms is confirmed by comparing STM images collected as a function of tip bias with images for the calculated structure by the Bardeen method.
†Department of Chemistry and Biochemistry and Laboratory for Surface Studies, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, United States.
John
J
Kestell
†Department of Chemistry and Biochemistry and Laboratory for Surface Studies, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, United States.
Rasha
R
Abuflaha
‡Brookhaven National Laboratory, Center for Functional Nanomaterials, Upton, New York 11973, United States.
J Anibal
JA
Boscoboinik
†Department of Chemistry and Biochemistry and Laboratory for Surface Studies, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, United States.
Michael
M
Garvey
†Department of Chemistry and Biochemistry and Laboratory for Surface Studies, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, United States.
Dennis W
DW
Bennett
†Department of Chemistry and Biochemistry and Laboratory for Surface Studies, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, United States.
Wilfred T
WT
Tysoe
1,4-phenylene diisocyanide; Au(111); reflection−absorption infrared spectroscopy; scanning tunneling microscopy; self-assembly