Computational simulations aimed at resolving a debate about how molecules bond to metal surfaces could help pave the path to smaller, faster and more powerful electronic devices such as MP3 players. Oak Ridge National Laboratory researchers De-en Jiang, Bobby Sumpter and Sheng Dai are using these simulations to model the bonding between aryl groups — the organic molecules with a flat ring of carbon atoms — and various metal surfaces. Their work helps in predictions for the most likely bonding configurations of molecules on various metal surfaces and helps answer the question of whether the aryl-metal bond is chemical or physical in nature. This is an important distinction for molecular electronics because chemical bonds are ideal electronic connections between molecular circuit elements. The researchers' simulations calculated the electron adsorption energies, which are a measure of the bond strength between the aryl carbon atoms and the metal surface. The calculations were performed using computers at the National Center for Computational Sciences. This research, which was funded by DOE's Office of Basic Energy Sciences, is published in the Journal of the American Chemical Society as a Communication.