Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Measuring Electron Orbitals

A recent SCIENCE paper sheds a new light on electron density in individual molecular states
A recent SCIENCE paper sheds a new light on electron density in individual molecular states

Abstract:
For the first time, it has been possible to measure electron density in individual molecular states using what is known as the photoelectric effect. Now published in SCIENCE, this method represents a key building block in the development of organic semiconductor elements. Supported by the Austrian Science Fund FWF, the success of this project rested on the mathematical transformation of the measured data. This made it possible to interpret the distribution of the electrons and draw conclusions about the potential properties of organic semiconductor elements.

Measuring Electron Orbitals

Austria | Posted on November 16th, 2009

Ultra-thin films made of organic molecules form the basis of future semiconductor technologies. Because organic molecules are extremely flexible, they can be used in a whole new range of applications, making it equally possible to create pliable screens and cost-effective solar cells. However, apart from these everyday applications for organic semiconductors, the most important task is to gain a better understanding of the interactions between organic materials and inorganic carrier substances. A team from the Universities of Graz and Leoben has now succeeded in developing a means of doing just that.

Tightly Packed

"The properties of an organic molecule are defined to a large extent by specific electron states", explains Dr. Peter Puschnig of the Chair of Atomistic Modelling and Design of Materials at the University of Leoben, who led the research. He adds: "If we can determine their distribution within the molecule accurately, then we will be able to better understand how organic semiconductor components work and thus increase their efficiency." Until now, there has been a lack of effective methods of measuring this electron distribution. Dr. Puschnig and his team have therefore succeeded in making significant progress.

The team's achievement is based on the use of the photoelectric effect. This enables individual electrons to be "knocked out" of organic molecules. As part of this project, an organic molecule was exposed to ultraviolet light that emitted sufficient energy to separate individual electrons from the molecules. The direction and speed of the electrons thus released were then measured using highly-sensitive detectors, generating the basic data required to calculate the electron distribution within the molecule. As part of this process, Prof. Michael Ramsay and his team from the University of Graz used a hexaphenyl film just one molecule thick that had been applied to a copper surface. The team from Graz carried out the actual measurements at the Berliner Elektronen-Speicherring Gesellschaft für Synchrotronstrahlung (BESSY, Berlin Electron Storage Ring Society for Synchrotron Radiation).

A Calculated Result

Commenting on the evaluation of this data, Dr. Puschnig says: "It revealed a quite characteristic distribution of the electrons emitted. However, it initially proved difficult to interpret this distribution and it seemed it would be impossible to link the measured data to the original electron distribution in the molecule." It was only by using special mathematical transformations (Fourier Transformation) that the team was able to establish that the measured electron distribution matched that of the molecule. As the distribution was in this instance already known from calculations carried out as part of the density functional theory, it was possible to test and confirm the viability of the new method.

This new method is particularly valuable as it means measuring the behaviour of electrons at the interfaces between organic semiconductors and metals is now relatively easy and highly accurate. The study "Interface controlled and functionalised organic thin films" supported by the FWF as part of the National Research Network (NFN) is thus making a fundamental contribution to future applications of organic semiconductors.

Original publication: Reconstruction of Molecular Orbital Densities from Photoemission Data, P. Puschnig, S. Berkebile, A. J. Fleming, G. Koller, K. Emtsev, T. Seyller, J. D. Riley, C. Ambrosch­Draxl, F. P. Netzer, M. G. Ramsey: Science 326, 702 (2009).

####

About Austrian Science Fund
The Austrian Science Fund (FWF) is Austria's central funding organization for basic research.

The purpose of the FWF is to support the ongoing development of Austrian science and basic research at a high international level. In this way, the FWF makes a significant contribution to cultural development, to the advancement of our knowledge-based society, and thus to the creation of value and wealth in Austria.

For more information, please click here

Contacts:
Scientific contact
Dr. Peter Puschnig
University of Leoben
Chair for Atomistic Modelling and Design of Materials
Austria
T +43 / 3842 / 402 4403


Austrian Science Fund (FWF)
Stefan Bernhardt
Haus der Forschung
Sensengasse 1
1090 Vienna
Austria
T +43 / 1 / 505 67 40 - 8111


Editor/publisher
PR&D - Public Relations for Research & Education
Campus Vienna Biocenter 2
1030 Vienna
Austria
T +43 / 1 / 505 70 44

www.prd.at

Copyright © Austrian Science Fund

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Basque researchers turn light upside down February 23rd, 2018

Stiffness matters February 23rd, 2018

Imaging individual flexible DNA 'building blocks' in 3-D: Berkeley Lab researchers generate first images of 129 DNA structures February 22nd, 2018

'Memtransistor' brings world closer to brain-like computing: Combined memristor and transistor can process information and store memory with one device February 22nd, 2018

Thin films

A simple new approach to plastic solar cells: Osaka University researchers intelligently design new highly efficient organic solar cells based on amorphous electronic materials with potential for easy printing January 28th, 2018

Scientists reveal the fundamental limitation in the key material for solid-state lighting January 25th, 2018

Particle size matters for porous building blocks: Rice University scientists find porous nanoparticles get tougher under pressure, but not when assembled December 19th, 2017

MIPT scientists revisit optical constants of ultrathin gold films October 20th, 2017

Govt.-Legislation/Regulation/Funding/Policy

Imaging individual flexible DNA 'building blocks' in 3-D: Berkeley Lab researchers generate first images of 129 DNA structures February 22nd, 2018

'Memtransistor' brings world closer to brain-like computing: Combined memristor and transistor can process information and store memory with one device February 22nd, 2018

Arrowhead Receives Regulatory Clearance to Begin Phase 1 Study of ARO-AAT for Treatment of Alpha-1 Liver Disease February 22nd, 2018

Computers aid discovery of new, inexpensive material to make LEDs with high color quality February 20th, 2018

Possible Futures

Basque researchers turn light upside down February 23rd, 2018

Stiffness matters February 23rd, 2018

Developing reliable quantum computers February 22nd, 2018

Imaging individual flexible DNA 'building blocks' in 3-D: Berkeley Lab researchers generate first images of 129 DNA structures February 22nd, 2018

Chip Technology

Basque researchers turn light upside down February 23rd, 2018

Imaging individual flexible DNA 'building blocks' in 3-D: Berkeley Lab researchers generate first images of 129 DNA structures February 22nd, 2018

'Memtransistor' brings world closer to brain-like computing: Combined memristor and transistor can process information and store memory with one device February 22nd, 2018

Photonic chip guides single photons, even when there are bends in the road February 16th, 2018

Nanoelectronics

Basque researchers turn light upside down February 23rd, 2018

Graphene on toast, anyone? Rice University scientists create patterned graphene onto food, paper, cloth, cardboard February 13th, 2018

Vanadium dioxyde: A revolutionary material for tomorrow's electronics: Phase-chance switch can now be performed at higher temperatures February 5th, 2018

Measuring the temperature of two-dimensional materials at the atomic level February 3rd, 2018

Announcements

Basque researchers turn light upside down February 23rd, 2018

Stiffness matters February 23rd, 2018

Histology in 3-D: New staining method enables Nano-CT imaging of tissue samples February 22nd, 2018

Developing reliable quantum computers February 22nd, 2018

Tools

Basque researchers turn light upside down February 23rd, 2018

Histology in 3-D: New staining method enables Nano-CT imaging of tissue samples February 22nd, 2018

Imaging individual flexible DNA 'building blocks' in 3-D: Berkeley Lab researchers generate first images of 129 DNA structures February 22nd, 2018

MEMS chips get metatlenses: Combining metasurface lenses with MEMS technology could add high-speed scanning and enhance focusing capability of optical systems February 21st, 2018

Solar/Photovoltaic

A simple new approach to plastic solar cells: Osaka University researchers intelligently design new highly efficient organic solar cells based on amorphous electronic materials with potential for easy printing January 28th, 2018

Tweaking quantum dots powers-up double-pane solar windows: Engineered quantum dots could bring down the cost of solar electricity January 2nd, 2018

Record high photoconductivity for new metal-organic framework material December 15th, 2017

Inorganic-organic halide perovskites for new photovoltaic technology November 6th, 2017

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project