IBM scientists measure molecular charge distribution

IBM scientists have measured for the first time how charge is distributed within a single molecule of naphthocyanine. Alongside bringing fundamental insights into single molecule switching and bond formation between atoms and molecules, the researchers say it introduces the possibility of imaging the charge distribution within functional molecular structures. They add the move could help to realise molecular scale computing devices. The scientists, from IBM Research in Zurich, imaged the charge distribution within a naphthalocyanine molecule using Kelvin probe force microscopy at low temperatures and in an ultrahigh vacuum. Although atomic force microscopy (AFM) can be used for resolving molecular structure, it has not been possible to image the charge distribution within a single molecule. "The technique provides another channel of information that will further our understanding of nanoscale physics," said Fabian Mohn, pictured, of the Physics of Nanoscale Systems group at IBM Research – Zurich. "It will now be possible to investigate at the single molecule level how charge is redistributed when individual chemical bonds are formed between atoms and molecules on surfaces. This is essential as we seek to build atomic and molecular scale devices."