Within the last few years, we've been treated to images of single molecules along with images of orbiting electrons. Today, IBM research has released a new image of a molecule, with enough detail that you can spot differences in the bonds between the individual atoms. Whoa.
This image (we're calling it an image because it's not a picture taken with visible light) shows a nanographene molecule. The molecule is made up of carbon atoms located at the junctions of those straight lines, and the lines are the atomic bonds themselves. If you look very, very closely, you'll notice that some of the carbon-carbon bonds are shorter than others.
This is because the bonds are stronger (they have a higher bond order), and for the first time, we can actually see it well enough to distinguish the different types of bonds from one another, visually. What this means is that we're looking at differences in features that are just three picometers in size, which works out to be about one-hundredth of the diameter of an atom. Here's another nanographene image which shows these bond differences even more clearly:
The instrument that can resolve features this detailed is called an atomic force microscope (AFM), and it uses a molecule of carbon monoxide to trace out tiny details in other molecules. By moving the carbon monoxide molecule back and forth and measuring how it wiggles, the AFM can slowly build up a very detailed image, sort of like making a topographic map. Here's an animation from IBM showing how it works:
It's fairly incredible to see that all this stuff that we learned in physics and chemistry about how atomic bonding works is actually how it works inside real molecules. All those chalkboard drawings that you obediently copied down into your notes aren't just some sort of hypothetical representation of the real world: as we've just seen, the real world looks just like we've been pretending it does all this time. Phew.