Skip to content.

TUD

search  |  internal  |  deutsch
Personal tools
TU Dresden » Faculty of Mechanical Science and Engineering » Institute for Materials Science » Chair of Materials Science and Nanotechnology



Thursday, 17 January 2008
(at 16:30 in room 115, Hallwachsstr. 3)
Add to your Google Calendar


Scanning tunnelling microscope investigation of elementary excitations

Karina Morgenstern


Universität Hannover
  Germany  






The tip of a scanning tunnelling microscope (STM) can be viewed as a highly localized electron beam, whose energy can be tuned by the applied voltage. The inelastic part of this electron beam might excite vibrations of surfaces or of adsorbed molecules. By this, it is possible to measure vibrations and to induce chemical reactions. Implementation of this method demands imaging at low temperature (5K) with submolecular resolution, in order to identify molecular side groups and position the tip exactly above a specific part of the molecule. In this talk, I will present vibrational spectra of individual water molecules adsorbed on Au(111) and the pure Au(111) surface. The reaction is exemplified on the rearrangement of hydrogen bonds within ice clusters and on the isomerisation of substituted benzene molecules. The energy dependence of the induced reactions allows determination of the excitation mechanism. Femtosecond laser pulses are a second means to produce high energetic electrons close to adsorbed molecules. The combination of a femtosecond laser with a STM allows investigating reactions locally. This will be demonstrated for CO/Cu(111).

Invited by G. Cuniberti and R. Gutierrez (nanoSeminar)

last modified: 2019.01.18 Fr
author: webadmin

contact
Prof. Dr. Gianaurelio Cuniberti
secretariat:
Ms Sylvi Katzarow
phone: +49 (0)351 463-31420
fax: +49 (0)351 463-31422
office@nano.tu-dresden.de
postal address:
Institute for Materials Science
TU Dresden
01062 Dresden, Germany
visitors and courier address:
HAL building
TU Dresden
Hallwachsstr. 3
01069 Dresden, Germany
Max Bergmann Center
TU Dresden
Budapester Str. 27
01069 Dresden, Germany