Format

Send to

Choose Destination
See comment in PubMed Commons below
Science. 2009 Aug 28;325(5944):1110-4. doi: 10.1126/science.1176210.

The chemical structure of a molecule resolved by atomic force microscopy.

Author information

1
IBM Research, Zurich Research Laboratory, 8803 Rüschlikon, Switzerland. lgr@zurich.ibm.com

Abstract

Resolving individual atoms has always been the ultimate goal of surface microscopy. The scanning tunneling microscope images atomic-scale features on surfaces, but resolving single atoms within an adsorbed molecule remains a great challenge because the tunneling current is primarily sensitive to the local electron density of states close to the Fermi level. We demonstrate imaging of molecules with unprecedented atomic resolution by probing the short-range chemical forces with use of noncontact atomic force microscopy. The key step is functionalizing the microscope's tip apex with suitable, atomically well-defined terminations, such as CO molecules. Our experimental findings are corroborated by ab initio density functional theory calculations. Comparison with theory shows that Pauli repulsion is the source of the atomic resolution, whereas van der Waals and electrostatic forces only add a diffuse attractive background.

PMID:
19713523
DOI:
10.1126/science.1176210
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Support Center