AVS 47th International Symposium
    Processing at the Nanoscale/NANO 6 Tuesday Sessions
       Session NS+NANO6+SS+MC-TuA

Paper NS+NANO6+SS+MC-TuA6
Chiral Surface Reconstruction by Largish Molecules

Tuesday, October 3, 2000, 3:40 pm, Room 302

Session: Self-assembly and Self-organization
Presenter: M. Schunack, University of Aarhus, Denmark
Authors: M. Schunack, University of Aarhus, Denmark
L. Petersen, University of Aarhus, Denmark
A. Kühnle, University of Aarhus, Denmark
E. Laegsgaard, University of Aarhus, Denmark
I. Steensgard, University of Aarhus, Denmark
F. Besenbacher, University of Aarhus, Denmark
Correspondent: Click to Email
Temperature-controlled scanning tunneling microscopy studies provide insight into the bonding, ordering and mobility of large organic molecules at metal surfaces. This is illustrated by investigations of disc-like molecules on a Cu(110) surface with a variable temperature STM, which can be operated down to 25 K.@footnote 1@ Hexa-tert-butyl decacyclene (HtBDC) self-assembles upon deposition onto Cu(110) above 250 K and forms a double-row structure in two directions surrounded by fast-diffusing single molecules. Nano-manipulation experiments with the STM at low temperatures revealed an underlying chiral reconstruction of the Cu surface. This consists of holes of approximately 14 Cu atoms pulled out of the surface. Surprisingly, the observed reconstruction is chiral. By gently annealing of the molecule structure at higher coverages, large enantiomerical pure domains with two different orientations build up. By means of simple effective medium theory calculations, we estimate the lower bound of the adsorption energy to be E@sub ad@ = 0.45 eV, and can give a plausible explanation for the observed structure. @FootnoteText@ @footnote 1@ L. Petersen, M. Schunack et al., submitted to Review of Scientific Instruments.