Letters: November 2025

Technology in transition

I read with great interest the articles by Phillip Broadwith (‘Biofuels burning out’) and Julia Robinson (‘UK biofuels production collapsing in face of cheap imports’). Both pieces commendably capture the challenges facing these critical industries, and the policy vacuum created by ill-conceived and poorly aligned government strategy – irrespective of the tie colour in office.

However, I believe an opportunity was missed to highlight the importance of these industries in providing fossil-free alternatives within a pragmatic, technology-neutral transition. While electrification is rightly a key pillar of defossilisation, Broadwith’s suggestion that biofuels offer only ‘small benefits’ risks oversimplifying the issue into a binary choice between electrification and nothing. In practice, we should pursue the right technology, not the right ideology.

The UK and EU vehicle fleets will remain dominated by hybrid and internal-combustion engine vehicles for many years. Sustainable fuels therefore provide an immediate, scalable means to reduce emissions, complementing electrification rather than delaying it. Moreover, the carbon footprint of electric vehicle manufacture and infrastructure development warrants the same scrutiny often applied to liquid fuels.

Robinson’s article offered a strong overview of the sector, lifecycle analysis, and the significance of policy frameworks such as the UK’s Renewable Trasport Fuel Obligation. Yet the broader value of these facilities – their role in supporting agriculture, generating biogenic carbon dioxide for essential industries, and forming the basis for future sustainable aviation fuels – deserves greater recognition.

The UK’s current policy approach risks outsourcing both emissions and opportunity. A more coherent framework – one that values domestic innovation and lifecycle carbon efficiency – would allow electrification and sustainable fuels to work in concert rather than competition.

Thank you though, for covering this important topic. The articles deserve wider circulation given their importance, in my view.

Luke Goldsmith MRSC
Via email

It’s a kind of magic

Congratulations to Victoria Atkinson on her fascinating article ‘The science behind the spells’. Interestingly, she uses one well-known phrase that deserves closer investigation.

The expression ‘just a placebo’ masks a very real phenomenon, one that is highly relevant to the overlap between chemistry, biology and health. While the fate of many a promising drug is sealed after a ‘no better than placebo’ verdict in a clinical trial, the general disappointment hides an astounding fact: that the ‘inactive’ agent (or at least the accompanying razzmatazz) is actually efficacious. Of course, very often the molecule in question has been designed to treat non-communicable conditions, diseases that may well be brought about by ‘dysbiosis’, a malfunctioning microbiome.

While the expression gut–brain axis is becoming more scientifically accepted, our studies lean towards an enlarged version: an ‘immune–gut–brain triangle’. In fact, it is possible that the microbiome is actually an intergenerational component of the immune system, closely associated with both gut wall and brain growth. Indeed, it seems that these phenomena are trying to tell us something fundamental about the ‘triple plagues’ of modern life (misdirected immune system, malfunctioning gut and poor mental health): that, rather than the organs themselves, disease is a function of inefficient inter-organ communication.

Accordingly, in the same way that exercise can have the triple benefit of improving mental health, increasing gut motility and stimulating the immune system, so the doctors in charge of double-blind clinical trials may ramp-up the placebo effect in their subjects, albeit inadvertently. Sadly, there is too little space here, but our work can be found on ResearchGate by searching for my name alongside the term ‘microbiome researcher’.

David Smith MRSC CChem
Alnwick, UK

DFT is dead. Long live DFT

Markus Reiher’s announcement of the death of density functional theory comes, I suspect, with a healthy dose of irony. There is a long history of developing methodologies to circumvent the time and expense of quantum chemistry and OMol25 is merely the next step. Impressive though this tool may be, however, any suggestion that we will suddenly switch off our workstations and do everything using a phone app misses the point.

For many of us, Reiher included, getting DFT to give us a decent structure is vitally important, and we love it dearly for that ability, but it is only a first step. To paraphrase Charles Coulson’s famous statement, it is just the number but it has no insight.

Answering the question of why the structure is as it is demands more than machine learning can provide. It requires testing ideas and hypotheses using virtual model systems, or distorted versions of known systems, secure in the knowledge that DFT will give us reliable geometries and energies and that none of this kind of data will come out of OMol25. In short, our imaginations will keep DFT alive and well.

Robert Deeth MRSC
University of Warwick, UK

Calculated expense

When reading Edward Neal’s article and seeing his reference to ‘brandishing a mere calculator’ I recalled how, over quite a short period, electronic calculators went from being a significant investment to being of fairly trivial financial worth.

In my undergraduate days in the early to mid 1970s, a calculator was seen as being too expensive for a student to purchase. I recall however that calculators were available for use in the teaching labs. Each one was mounted on a piece of wood which was chained to the bench.

When I was a graduate student I had the use of a calculator that belonged to the department. That was a privilege, and I in turn was expected to ensure its security by leaving it out of sight in a drawer when it was not in use.

Moving forward to the late 1970s and early 1980s when I was in my first academic job, each of my students would have had a personally owned calculator. At one of the campus retail outlets a very basic calculator, probably capable just of addition, subtraction, multiplication and division, was offered as a ‘free gift’ with some purchases.

Clifford Jones FRSC
University of Chester, UK 

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