First ‘molecular image’ created by IBM

IBM has created the first ever direct image of a molecule, using a piece of tech known as an atomic force microscope to image a pentacene molecule in unprecedented detail. Below there are two images; one is a rendered model of the pentacene molecules, the other is the image of the molecule as captured by the atomic force microscope:

Keep reading for my explanation of why this so totally fucking crazy.

In a traditional microscope,  the image you see occurs because light reflects off of, or passes through, the object you’re trying to image.  The light from the object that arrives at your imaging device is what causes the image.  This only works down to a certain scale, which is constrained by the wavelength of the light you’re using.  Anything smaller than that wavelength simply can’t be resolved.  Newer technologies, like electron microscopes, use a similar principle, but a different transmission medium than light.  The result is the same, the size of the object you can image is constrained by the wavelength of whatever you’re using.

Trying to image something as small as a molecule is impossible with these kinds of microscopes.  They are far smaller than the wavelengths of either visisble light or electron waves, and in the case of an electron microscope, the stream of electrons are likely to tear the molecule apart.  For a long time, it was accepted that direct imaging of an object on the molecular scale was simply impossible.

The atomic force microscope makes this kind of tiny-scale imaging possible because it doesn’t use a transmission medium (for lack of a better term) like light or electron waves.  It’s actually a small probe that detects tiny changes in the electromagnetic force field around the molecule.  It’s not actually “seeing” the molecule, just making a map of the forces surrounding it.  So the picture of above isn’t a picture of the molecule in a traditional sense, but it can be translated into an image based on the measurements taken from the probe.

And what an image!  I was blown away when I first saw it, because of how perfectly the structure of the molecule matches our modelling of it (or should that be the other way around?).  The hexagonal shape of the benzene-like rings is perfect, the bonds going to the hydrogen atoms stick straight out, and there’s a clear difference in the field strength/direction between the centre and ends of the molecule.  If I’m not mistaken, some of the fuziness around the outside of the molecule corresponds to electrons and their favoured position at the peripherals of the molecule’s influence.  All pretty crazy, considering the molecule is only 1.4 nm across!

[Thanks to Gizmodo and Starts with a Bang for the story - check out the mirror on w0rd!]