‘I work with crystals – but it’s not what you think’

Based in the department of chemistry and polymer science at Stellenbosch University in South Africa, Professor Delia Haynes’ research and expertise focuses on crystals. But it’s prone to assumption: “When I say to people, ‘I work with crystals’, often the response I get is something about crystal healing.”

This is very different to what Delia actually does: “Crystals pop up everywhere, and the types of crystals I work with are the types found in pharmaceutical drugs. Crystals are simply solids where the molecules inside are arranged in a repeating pattern. The drug paracetamol is in a crystalline form, Delia says, “in fact many drugs are crystals – almost all the drugs that you would take in a pill or capsule are actually in their crystal form; the crystals are just very small. Table salt and sugar are also crystals. The silicone used in electronic chips in your phone etc are also crystals – pure solid forms.”

Many crystals, such as amethyst, carnelian and jasper, are formed through geological processes. All crystals, whether found in the earth’s crust or not, follow a basic set of rules: “What is different between those [geological] types of crystals and the crystals I work on,” Delia says, “is that those are classically ‘inorganic’ crystals…they’ve got silicon, oxygen [and] metals in them, whereas what I tend to work on contain organic materials – carbon, oxygen, hydrogen, nitrogen [and] quite a lot of sulphur and fluorine as well.”

Choosing an area of expertise

At university Delia planned to specialise in genetics. But studying it alongside other sciences convinced her otherwise. Instead, she decided to pursue post-graduate work in chemistry: “I just really enjoyed [it] the whole way through.” Ready to venture out of South Africa, she applied for places and funding in the UK. When it all came together: “I landed up doing MPhil at Cambridge, then a PhD at Cambridge and then a postdoc at Cambridge. So that was six years of my life.” 

Delia became interested in crystallography during her PhD: “My supervisor was doing a lot of work with crystals. And so that became part of my work: looking at crystals, determining [their] structure.” Again she really enjoyed it, and found she was drawn to the precise way molecules arrange themselves: “I’ve actually always been fascinated by patterns and by symmetry; I just never thought about it as a thing to bring into my job.”

After returning to South Africa, a position opened up in her field of research at Stellenbosch University, near Cape Town: “The top researcher in the country at the time was at Stellenbosch…There were people working in my area, and the equipment was here, so it seemed like a good move to make. And I’m still here.”

Faith permeating life

Born into a Catholic family, Delia’s faith had no obvious starting point and gently permeates everything she does – her work included. It was involvement in a production of Godspell when she was a teenager that gave her a deeper understanding of the humanity of Jesus. Then while at university in 1997 she did an Alpha course: “I did the course with a group of people from different denominations. It was eye-opening as I learned how active God is in everyone’s day-to-day life.” Delia continued to pursue her relationship with God and did another Alpha course in the UK when a student again, and then over a decade ago she did another back in South Africa. “That Alpha course group was just ladies, and we became a Bible study group that I attended until I moved to Stellenbosch about five years later. Those women were a great support to me and I miss them!”

“Many scientists are not people of faith” she reflects, “[but] I can be a witness in a quiet way by just going, ‘Well, I am Christian, and I’m still a scientist…let’s talk about it.’ It’s really an opportunity to open a space for people to talk…those conversations do happen, and they’re always useful and interesting.”

Researching the properties of crystals

Delia’s work involves crystal engineering: “It’s engineering the arrangement of the molecules in the crystal to try and get a particular target property for your application.” By changing the pattern of molecules in a crystal, you can change its properties: its colour, melting point and how fast it dissolves and these all affect how it can be used. “One of the places where we use crystals in our daily life all the time is pharmaceuticals”, says Delia. Understanding how or why molecules arrange themselves in a certain pattern is essential: “if you change that crystal form it will change the way your pharmaceutical behaves”. 

I’ve always been fascinated by patterns and by symmetry

Her research group has multiple areas of interest. One is how molecules can line up to produce magnetic properties – their inherent positive and negative charges making this possible. Another is ‘multi-component crystals’: “so more than one molecule crystallising together in a crystal”. Other research has included crystals that are porous: “crystals that behave as sponges – they have holes in them that you can use to selectively absorb other molecules”. And more recently how growing a crystal straight from a gas (called sublimation) affects it differently to growing it from a solution. While they can’t position individual molecules “like Lego bricks”, at a molecular level, scientists can see how different factors affect their arrangement. “The most critical piece of equipment that we use is called an X-ray diffractometer” she says. “If we measure the pattern of the [X-ray] light that is diffracted [through the crystal], we can use computer software to tell us how the molecules are arranged.” AI, too, has become a useful tool for predicting potential patterns and outcomes of crystal engineering, though for Delia hands-on lab work will always come first.

The scientific method is at once rigorous and responsive; constantly incorporating new data: “Science is based on models”, says Delia, “[they] describe what we think is happening”. Models are tested through making predictions and doing experiments. And any result or statement made is interrogated: “What are the assumptions? Could there be something that we need to look at in more detail there?” she says, “You need to be questioning all the time.”

Faith and science

Evidence is essential, but science doesn’t help Delia to understand God. “Using that method of proof is not helpful”, she says. For Delia, God is “not God of the gaps”. This theological idea ascribes gaps in scientific discovery to the existence of God: “It cannot be helpful to explain that God is amazing, based on some physical phenomenon, because then, if we find a scientific explanation for that physical phenomenon, we have a problem.” For example; if the parting of the Red Sea was discovered to be nothing more than a geological phenomenon: “Does my belief in God then collapse? [Instead] I want to base my belief in God on what I see [him] doing in the world…and on what others tell me they experience of God.”

Does science require belief? “Yes, you do have to believe things”, she says. Even when there is substantial evidence, a degree of belief is required: “I have never seen an atom, but I do believe that they exist, and I have to.” Belief also extends to the veracity of work done by other scientists: “unless you want to repeat every experiment that’s ever been done”; though even the most revered work must be questioned.

So what’s next? Delia is considering the bonding between molecules in a crystal: “You would think that we understand what a bond is by this stage. But we don’t completely. We’re not finished…and there’s some really exciting potential there for the future.” 

As for God’s creation of crystals, Delia has recently been on a women’s retreat and, while there, had an experience of God where he showed her how close he was, how he cared about her and was excited about the world he created – what is possible and how amazing his creation is. Genesis 1:31 says :“God saw all that he had made, and it was very good.” Delia says: “To be able to study a tiny portion of God’s creation is a gift.”