The Challenges of Chemistry Illustration

As an artist and a chemist, I’ve always found it very interesting that chemistry is so hard to illustrate.  In physics you can draw pretty good diagrams, and in biology illustration can often be done through observation.  Note that I’ve never taken advanced classes in physics or biology – perhaps the more advanced material is truly hard to represent.  But that seems to be the norm in chemistry…things just can’t be drawn as they are.

Let’s take Lewis structures.  Drawing a few atoms with lines between them is a pretty good representation of bonds, right?  It works okay (ish) for single bonds… But for double and triple bonds, Lewis structures aren’t very representative of the structures that exist.  A trio of parallel lines doesn’t intuitively convey that there are two orbitals overlapping head-on to form one sigma bond, and two sets of p orbitals parallel to each other forming 2 pi bonds.  Also, these kinds of structures don’t do conjugation and resonance justice – as in class, one must draw multiple structures or dotted lines to convey “partial double bonds” or “resonance structures” when in reality, the bond in question is neither single nor double.  The electrons that make up the bond are simply delocalized; they can move around between multiple atoms in an orbital that isn’t in the shape of that simple little line on the Lewis structure diagram.

Let’s go even smaller – how does one illustrate an electron?  Typically we draw them as little dots orbiting a nucleus.  I briefly mentioned orbitals in the previous paragraph; to expand on that, electrons do not orbit atoms.  They instead hang out around the nucleus in impossible-to-fully-determine patterns (I’m looking at you, Heisenberg), and certain electrons of certain energies are found ~95% of the time in certain areas.  Those areas are called orbitals.  We can illustrate the orbitals with complex computer programs, but what about the electrons themselves?  We’ve established that they’re not orbiting anything; are they even little dots?  Inevitably, no, they are not.  Electrons are just like light – sometimes they act like particles and sometime they act like waves.  In reality, they’re both.  This is actually true of ALL matter – we’re all sort of particles and sort of waves (thank de Broglie for that brain-bender).  The thing is, big objects have teeny tiny wavelengths, to the point that treating them as waves is a little pointless.  Because electrons are so small, their wavelengths are large enough to noticeably affect their properties.  And how is one meant to illustrate that accurately?  A teeny tiny whatever-it-is with hardly any mass that is both a wave and particle?  It just doesn’t work out.

Illustrating chemistry, then, is not a matter of making a representation that takes into account all knowledge possible, with the most accurate picture in mind.  This expectation is objectively impossible.  Instead, it seems to be about finding ways of illustrating things in ways that help us understand chemical properties.  Maybe Lewis diagrams aren’t so accurate, but they are a big help when you’re mapping out a molecule’s structure.  In this way, the illustrations have to be tools, like for teaching or writing in shorthand.  To use them, we have to constantly acknowledge where they are right and where they are wrong.  To create them, one has to keep an eye on the balance between accuracy and simplicity in order to create the best representation possible.  This will be my challenge over the summer: I will be working at making chemistry graphics for one of my professors.  It will be an interesting experience in illustrating that which cannot be illustrated 🙂