What do bonds look like?

Image created by Matthew Bird using Canva.
"Glass ochem dof2" by Purpy Pupple - Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons.

From secondary school onwards we are taught that the world around us in made from atoms and those atoms are held together by bonds. As we get older we are introduced to the different types of bond: covalent, ionic, and metallic. We are also told about hydrogen-bonds, though these don't join atoms together as the other types do.

We are all used to the diagrams we see for bonding, but is that what an actual bond looks like? Until recently the answer was a decisive, 'we don't know'. No one, not even scientists, had ever seen a bond. No one had ever seen an atom. We had calculations and theories saying they were there, but no actual visual of them until recently.

In the first 'Images on Monday' post, let's be curious and ask 'what does a bond look like?'

First image of covalent bonds
cen.acs.org, Credit: IBM Research, Zurich

This is one of the first images of chemical bonds. Researchers produced this image using an atomic force microscope with a tip containing a single carbon monoxide molecule.

The image may look simple but it is, in many ways, beautiful. The image shows not just atomic bonds, but also that they look much the same as we expected. The image shows the theoretical science works. The bonds shown in the image are covalent bonds.


It took longer for the first images of hydrogen bonds to be produced using a similar technique. The molecule 8-hydroxyquinoline was used to create this next image because it is flat, and 'its one hydrogen bond is out of the plane of the structure'. (rsc.org)

First images of a hydrogen bonds in 8-hydroxyquinoline (left). Computer model of 8-hydroxyquinoline.
www.rsc.org/, image copyright of Science/AAAS

You can see covalent bonds in this image (the stronger white bonds), but also hydrogen bonds (the weaker white bonds in the black area). The model on the right matches the orientation of the image on the left, so you can follow which atom is where fairly easily. Green is carbon, white is hydrogen, red is oxygen, and blue is nitrogen.

Again, this image is quite stunning. Everything matches up with what we'd expect. It's almost like being completely blind, and using only touch and working out what things look like, and then suddenly getting sight and being completely correct.

Curious Fact

The first images of bonds were created by researchers at IBM (International Business Machines) in 2009.

What do you think of the images? Like, +1, tweet, and comment on this post below and using the social media tools to the left. Follow It Is All Science using the buttons on the right.

Can you guess next Monday's image? Here's a clue: It gives you some perspective. Let me know in the comments below if you can guess what image I will be posting.

Remember, it is all science. So, let's be curious.