Cooperative mechanism for anchoring highly polar molecules at an ionic surface

Autor(en): Schuette, J.
Bechstein, R.
Rohlfing, M.
Reichling, M. 
Kuehnle, A.
Stichwörter: BASES; DIFFRACTION DATA; DIFFUSION; FORCE MICROSCOPY; GROWTH; INDIVIDUAL MOLECULES; INSULATING SURFACES; Materials Science; Materials Science, Multidisciplinary; METAL-SURFACES; ORGANIC-MOLECULES; Physics; Physics, Applied; Physics, Condensed Matter; PTCDA
Erscheinungsdatum: 2009
Herausgeber: AMER PHYSICAL SOC
Journal: PHYSICAL REVIEW B
Volumen: 80
Ausgabe: 20
Zusammenfassung: 
Structure formation of the highly polar molecule cytosine on the (111) cleavage plane of calcium fluoride is investigated in ultrahigh vacuum using noncontact atomic force microscopy at room temperature. Molecules form well-defined trimer structures, covering the surface as homogeneously distributed stable structures. Density-functional theory calculations yield a diffusion barrier of about 0.5 eV for individual molecules suggesting that they are mobile at room temperature. Furthermore, it is predicted that the molecules can form trimers in a configuration allowing all molecules to attain their optimum adsorption position on the substrate. As the trimer geometry facilitates hydrogen bonding between the molecules within the trimer, we conclude that the stabilization of individual diffusing molecules into stable trimers is due to a cooperative mechanism involving polar interactions between molecules and substrate as well as hydrogen bonding between molecules.
ISSN: 10980121
DOI: 10.1103/PhysRevB.80.205421

Show full item record

Page view(s)

3
Last Week
0
Last month
0
checked on Mar 4, 2024

Google ScholarTM

Check

Altmetric