New Delhi: Carbon and boron are neighbours on the periodic chart, but only one of them is a celebrity in the scientific community. The other is notorious for its complexities. While most scientists understand the structural chemistry of carbon, relating methane to diamond and benzene to graphite, a young researcher ED Jemmis asked himself whether boron could also be understood in a similar way.
Now, nearly 48 years and many research papers later, Jemmis is closer to understanding boron in a way that is revolutionising the world of inorganic chemistry.
The latest breakthrough was reported in a recent study published in the journal Science. Researchers at the Indian Institute of Technology Madras (IITM) and Indian Institute of Science (IISc) in Bangalore have created an all-inorganic analog of ferrocene, bringing boron back to the public eye.
Ferrocene is a unique chemical compound where a single iron atom is “sandwiched” between two flat, five-carbon rings. It looks like a bright orange powder and is famous for being incredibly stable. It can even survive being heated to 400°C without breaking down. It was accidentally discovered by two separate research groups in 1951.
The material launched a new era of organic chemistry based on the study of carbon, and was used in catalysts, electrochemistry, medical and pharmaceutical research, and even as an additive to fuel to improve combustion.
But researchers were not satisfied. Many tried to replicate this particular chemical sandwich using boron instead of carbon. If they succeeded—which they now have—it would mean that not all complex structures are limited to a carbon-based chemistry.
Carbon’s lesser known neighbour
Even as boron is now stepping into a scientific spotlight of its own, Jemmis’ story with boron goes back to 1968 when he was a first year student doing a Bachelor of Science. From a masters at IIT Kanpur, to a PhD at Princeton, and back to being a professor at Hyderabad University, Jemmis’ commitment to boron never wavered.
“Boron is a complex subject,” Jemmis, a researcher at IISc for the past 20 years, told ThePrint. In the scientific community, carbon is much-studied, but many scientists have given up on trying to understand boron.
Unlike carbon which has six electrons that make it stable, boron has only five. One electron makes all the difference. It means boron often has to share electrons between three or more atoms to be structurally stable. Therefore, predicting how a boron molecule will react or bond with others requires advanced computing.
Jemmis agrees that computational advancements have made it easier to understand and predict the energetics of boron and its stability. But the mystery of boron is only slowly unfolding, finding relations between molecules of boron and its allotropes.
“Understanding comes after computation or experiment. Understanding means asking why the atoms behave a certain way—the general principles behind boron in the current instance,” said Jemmis.
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A collaboration with IIT-M
Meanwhile Professor Sundargopal Ghosh, one of the world’s leading metallaborane chemists, established an experimental laboratory in IIT Madras in the last 20 years, synthesizing molecules that stretch the understanding of structural chemistry of boron. Fifteen years ago, Jemmis and Ghosh began collaborating to understand such rule-breaking structure. Since then, they have published about ten articles, and this year, in April, they announced that they had managed to recreate that initial ferrocene sandwich but with a metal called osmium, not too different from iron, held together with rings made of boron and hydrogen. This is the outcome of several years of synthetic efforts at IIT-M.
As they heated an osmium compound with a boron-hydrogen system at 100 degrees Celsius, a colourless solid emerged. They then x-rayed the material to confirm the new ferrocene-like structure. Researchers found that not only was the material stronger than the carbon-based ferrocene, boron molecules could also connect to metals in more ways than one. What is equally interesting is that the experimentalists have also obtained an isomeric structure which is rarely thought of in the context of ferrocene.
“Just as ferrocene started a new era in organometallics, these results will start a new era in inorganometallics and will soon be a part of textbooks of inorganic chemistry. Our efforts are on to study the reactions of these new compounds,” Ghosh, one of the corresponding authors of the study, said in an IISc press release.
For now, the research is still fresh, and speculations about what it can potentially do are rife. But Jemmis is cautious.
“If someone asked me to comment on the discovery of ferrocene in 1952, all I would say is that it is an interesting structure,” said Jemmis. For now, the newly discovered material too is “an interesting structure”.
But Jemmis admits that there has been a significant change from 1982, when he first published a paper on boron and most academics found the subject irrelevant, to 2026, when the world may have finally woken up to the potential of boron-based research and materials, including borophenes and bilayer borophenes.
(Edited by Saptak Datta)