Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Clusters of Aluminum Atoms Found to Have Properties of Other Elements Reveal a New Form of Chemistry

14.01.2005


Artist’s rendition of an aluminum-iodine "Superatom" identified by the Castleman group at Penn State and the Khanna group at Virginia Commonwealth University. Credit: D.E. Bergeron, P.J. Roach, A.W. Castleman, N.O. Jones, and S.N. Khanna


A research team has discovered clusters of aluminum atoms that have chemical properties similar to single atoms of metallic and nonmetallic elements when they react with iodine. The discovery opens the door to using ’superatom chemistry’ based on a new periodic table of cluster elements to create unique compounds with distinctive properties never seen before. The results of the research, headed jointly by Shiv N. Khanna, professor of physics at Virginia Commonwealth University and A. Welford Castleman Jr., the Evan Pugh Professor of Chemistry and Physics and the Eberly Family Distinguished Chair in Science at Penn State University, will be reported in the 14 January 2005 issue of the journal Science.

"Depending on the number of aluminum atoms in the cluster, we have demonstrated ’superatoms’ exhibiting the properties of either halogens or alkaline earth metals," says Castleman. "This result suggests the intriguing potential of this chemistry in nanoscale synthesis." The discovery could have practical applications in the fields of medicine, food production and photography.

The researchers examined the chemical properties, electronic structure, and geometry of aluminum clusters both theoretically and experimentally in chemical compounds with iodine atoms. They found that a cluster of 13 aluminum atoms behaves like a single iodine atom, while a cluster of 14 aluminum atoms behaves like an alkaline earth atom. "The discovery of these new iodine compounds, which include aluminum clusters, is critical because it reveals a new form of ’superatom’ chemistry," said Khanna. "In the future, we may apply this chemistry, building on our previous knowledge, to create new materials for energy applications and even medical devices."


To make their discovery, the research team replaced iodine atoms with the aluminum clusters in naturally occurring chains or networks of iodine atoms and molecules known as polyiodides. When the researchers substituted the iodine atom with the aluminum cluster, Al13, they observed that the entire chemistry of the compound changed--causing the other iodine molecules to break apart and bind individually to the cluster. The researchers then were able to bind 12 iodine atoms to a single Al13 cluster, forming a completely new class of polyiodides. "Our production of such a species is a stirring development that may lead to new compounds with a completely new class of chemistry and applications," says Castleman. "Along with the discovery that Al14 clusters appear to behave similarly to alkaline earth atoms when combined with iodine, these new results give further evidence that we are really on our way to the development of a periodic table of the ’cluster elements’."

The researchers conducted experimental reactivity studies that indicate that certain aluminum-cluster superatoms are highly stable by nature. The team’s related theoretical investigations reveal that the enhanced stability of these superatoms is associated with a balance in their atomic and electronic states. While the clusters resemble atoms of other elements in their interactions, their chemistry is unique, creating stable compounds with bonds that are not identical to those of single atoms.

Using stable clusters provides a possible route to an adaptive chemistry that introduces the aluminum-cluster species into nanoscale materials, tailoring them to create desirable properties. "The flexibility of an Al13 cluster to act as an iodine atom shows that superatoms can have synthetic utility, providing an unexplored ’third dimension’ to the traditional periodic table of elements," said Khanna. "Applications using Al13 clusters instead of iodine in polymers may lead to the development of improved conducting materials. Assembling Al13I units may provide aluminum materials that will not oxidize, and may help overcome a major problem in fuels that burn aluminum particles."

The theoretical investigations for this project were conducted by Khanna with N.O. Jones, a graduate student in the physics department at Virginia Commonwealth University, and the experimental work was conducted by Castleman with Denis Bergeron and Patrick J. Roach, graduate students in the chemistry department at Penn State.

This research was supported by the U. S. Air Force Office of Scientific Research and the U. S. Department of Energy.

Barbara K. Kennedy | EurekAlert!
Further information:
http://www.psu.edu
http://www.vcu.edu

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Epoxy compound gets a graphene bump

14.11.2018 | Materials Sciences

Microgel powder fights infection and helps wounds heal

14.11.2018 | Health and Medicine

How algae and carbon fibers could sustainably reduce the athmospheric carbon dioxide concentration

14.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>