Scientists create the first synthetic nanoscale fractal molecule

May 11, 2006
Scientists create the first synthetic nanoscale fractal molecule
Scientists have created and captured an image of the largest man-made fractal molecule at the nanoscale. Credit: Saw-Wai Hla, Ohio University

From snowflakes to the leaves on a tree, objects in nature are made of irregular molecules called fractals. Scientists now have created and captured an image of the largest man-made fractal molecule at the nanoscale.

The molecule, developed by researchers at the University of Akron, Ohio University and Clemson University, eventually could lead to new types of photoelectric cells, molecular batteries and energy storage, according to the scientists, whose study was published online today by the journal Science.

A University of Akron research team led by Vice President for Research George Newkome used molecular self-assembly techniques to synthesize the molecule in the laboratory. The molecule, bound with ions of iron and ruthenium, forms a hexagonal gasket.

Chemical structure of the fractal molecule. Art by: Courtesy Saw-Wai Hla
Chemical structure of the fractal molecule. Art by: Courtesy Saw-Wai Hla

Ohio University physicists Saw-Wai Hla and Violeta Iancu, who specialize in imaging objects at the nanoscale, confirmed the creation of the man-made fractal. To capture the image, the physicists sprayed the molecules onto a piece of gold, chilled them to minus 449 degrees Fahrenheit to keep them stable, and then viewed them with a scanning tunneling microscope.

Though invisible to the naked eye – the molecules are about one million times smaller than the colorful hexagons shown in the Science image – the objects are 12 nanometers wide. "That's big for a nanoscale molecule. It's huge," said Hla, an associate professor of physics and astronomy.

"This man-made structure is one of the first nanoscale, non-branched fractal molecules ever produced," said Newkome, who is lead author on the Science paper and also serves as dean of the Graduate School and the James and Vanita Oelschlager Professor of Science and Technology at the University of Akron. "Blending mathematics, art and science, these nanoscopic hexagonal-shaped materials can be self-assembled and resemble a fine bead necklace. These precise polymers -- the first example of a molecule possessing a 'Star of David' motif -- may provide an entrée into novel new types of photoelectric cells, molecular batteries and energy storage."

Fractals are irregular curves or shapes that retain the same pattern when reduced or magnified. The molecule in the study, for example, is composed of six rings, which are made up of six smaller rings, and so on, Hla explained. Snowflakes, broccoli florets or tree bark would be just a few examples from nature.

Hla and Iancu, a graduate student, also were able to measure the electronic structure of the molecule, which is useful to know for possible electronic applications. "(The molecules) are unique in their own way, so you have to find out what kind of properties they have so we can initiate possible applications," he said.

The study authors were George R. Newkome, Pingshan Wang, Charles N. Moorefield, Tae Joon Cho, Prabhu Mohapatra, Sinan Li, Seok-Ho Hwang and Judith A. Palagallo, all from the University of Akron; Violeta Iancu and Saw-Wai Hla of Ohio University; and Olena Lukoyanova and Luis Echegoyen of Clemson University.

Source: Ohio University

Explore further: Small molecule plays big role in weaker bones as we age

Related Stories

Detangling DNA replication

September 18, 2018

DNA is a lengthy molecule—approximately 1,000-fold longer than the cell in which it resides—so it can't be jammed in haphazardly. Rather, it must be neatly organized so proteins involved in critical processes can access ...

Recommended for you

Engineers develop first method for controlling nanomotors

September 19, 2018

In a breakthrough for nanotechnology, engineers at The University of Texas at Austin have developed the first method for selecting and switching the mechanical motion of nanomotors among multiple modes with simple visible ...

Graphene tunnelling junctions: beyond the breaking point

September 19, 2018

Molecular electronics is a burgeoning field of research that aims to integrate single molecules as active elements in electronic devices. Obtaining a complete picture of the charge transport properties in molecular junctions ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.