IBM scientists in Switzerland have succeeded in imaging the chemical structure of a molecule using a technique known as non-contact atomic force microscopy (AFM).
The results could have a huge impact on the field of nanotechnology, particularly when designing electronics or developing pharmaceuticals.
"We are using the atomic force microscope to image the atomic structures that are the backbones of individual molecules," said IBM researcher Gerhard Meyer. "Scanning probe techniques offer amazing potential for prototyping complex functional structures and for tailoring and studying their electronic and chemical properties on the atomic scale."
The IBM researchers published their findings in Nature.
Leo Gross, Fabian Mohn, Nikolaj Moll and Gerhard Meyer, from IBM Research - Zurich, in collaboration with Peter Liljeroth of Utrecht University, used an AFM operated in an ultra-high vacuum and at very low temperatures (-268°C) to image the chemical structure of individual pentacene molecules. With the AFM, they were able, for the first time, to look through the electron cloud and see the atomic backbone of an individual molecule.
The AFM uses a sharp metal tip to measure the tiny forces between the tip and the sample, such as a molecule, to create an image. Pentacene is an oblong organic molecule consisting of 22 carbon atoms and 14 hydrogen atoms measuring 1.4nm in length. The spacing between neighbouring carbon atoms is only 0.14nm.
"The key to achieving atomic resolution was an atomically sharp and defined tip apex as well as the very high stability of the system," said Gross.
"We prepared our tip by deliberately picking up single atoms and molecules and showed that it is the foremost tip atom or molecule that governs the contrast and resolution of our AFM measurements."