IIT Mandi’s Distinguished Professor Gautam R. Desiraju Receives 14th Ewald Prize

Mandi: Professor Emeritus Gautam R. Desiraju has been awarded the 14th Ewald Prize by the International Union of Crystallography (IUCr) for pioneering the subject of crystal engineering and the supramolecular synthon concept, and for establishing the structural significance of weak hydrogen bonding and halogen bonding in molecular crystals and biology. The Ewald Prize, awarded once every three years at the International Congress of Crystallography, recognises outstanding contributions to the science of crystallography, and the 2026 laureate, on 11th August 2026, Gautam R. Desiraju, has been honoured at the IUCr Congress in Calgary, Canada.
Desiraju — an Emeritus Professor at the Indian Institute of Science, Bengaluru, and a Distinguished Professor at IKSMHA, IIT Mandi, among other affiliations — has described the honour in characteristically direct terms.
Reflecting on the award, Professor Emeritus Gautam R. Desiraju said, “The Ewald Prize is widely considered the highest accolade a structural chemist or biologist can receive, short of the Nobel Prize, singling out the complete professionalism of its rigorous and confidential selection process.”
Speaking upon this Prof. Laxmidhar Behera, Director, IIT Mandi, said, “Professor Desiraju’s Ewald Prize is a matter of immense pride for IIT Mandi and Indian science. His pioneering work in crystal engineering has transformed our understanding of molecular interactions and opened new possibilities in pharmaceuticals and advanced materials. We congratulate him on this well-deserved global recognition.”
To mark the award, Desiraju has published a lead article in IUCrJ (Volume 13, Part 5, September 2026) titled “Crystal clear. Engineering complexity,” an open-access, first-person retrospective on the field he helped found. The paper accompanies the prize and forms part of a collection tied to the IUCr 2026 Congress.
From “anomalous” crystals to a design science
The article traces a scientific journey that began during Desiraju’s PhD at the University of Illinois, where he was struck by a deceptively simple question: why do crystals adopt the structures they do? At the time, the prevailing view — associated with the physicist Kitaigorodskii — held that organic crystals were governed chiefly by close packing. Desiraju’s insight was to treat the exceptions as the key.
His attention turned to weak intermolecular forces, particularly the C—H···O interaction, which he and Thomas Steiner ultimately validated as a genuine weak hydrogen bond in their 1999 book. Once dismissed as insignificant, these interactions are now recognised as structurally and functionally important in both small-molecule crystals and biological systems.
The supramolecular synthon
The conceptual heart of the article — and of Desiraju’s legacy — is the supramolecular synthon, a term he defined in a landmark 1995 review. Borrowing from Corey’s retrosynthetic logic in molecular synthesis, Desiraju reframed the molecular crystal itself as a synthetic target, one that could be “disconnected” into structural modules assembled through predictable intermolecular interactions. This move, more than any other, positioned crystal engineering within the chemical mainstream as a form of synthesis rather than mere structural description.
The paper walks through how this thinking scaled up: from binary and ternary cocrystals built on insulated, hierarchically arranged synthons, to quaternary and even five- and six-component molecular crystals — what Desiraju calls the “Mount Everest of supramolecular solid state synthesis.”
Real-world payoffs and open questions
The article connects these ideas to tangible applications, most notably pharmaceutical cocrystals, which improve the solubility and bioavailability of poorly water-soluble drugs and have yielded around half a dozen marketed medicines built on crystal-engineered logic. It also covers polymorphism and crystal structure prediction — where Desiraju argues AI may fully solve the prediction problem within five to ten years — and a newer sub-branch on mechanically deformable crystals that bend, shear, or self-heal.
A holistic turn
The essay closes on a philosophical note that will resonate with readers interested in Indian Knowledge Systems. Desiraju frames the molecular crystal not as an assembly of parts but as a complex, holistic system, explicitly setting the integrative philosophies of older societies alongside Western reductionism. He argues that a functional crystal depends on a synergy between the rigidity of strong bonds and the adaptive subtlety of weak ones — and, extending the metaphor outward, on the “essential oneness” of a shared human intellect across cultures.
With more than 475 publications and over 80,000 citations, and having served as President of the IUCr from 2011 to 2014, Desiraju’s contributions have had a profound influence on structural chemistry and crystallography worldwide. The Ewald Prize now formally recognises a body of work that transformed crystal engineering from a curiosity into a predictive, design-oriented discipline.
About IIT Mandi:
Indian Institutes of Technology Mandi is one of the top second-generation IITs located in Kamand Valley, Mandi district of Himachal Pradesh, India. It is one of eight new Indian Institutes of Technology (IITs) established by the Ministry of Human Resource Development, Government of India, and recognized as one of Institutes of National Importance. IIT Mandi’s permanent campus about 14 km (8.7 mi) from Mandi consists of the South and North campuses connected by a narrow neck. The South campus is on the left bank of the Uhl River below Kamand village. The North campus is along the Kataula Khad opposite Salgi village. A transit campus at Government Post graduate College, Mandi was handed over by the Himachal Pradesh Government on 16 November 2009. The Kamand campus ground-breaking ceremony, to mark the start of construction, was held on 13 April 2012. On 25 April 2015, IIT Mandi became the first of all the new IITs to completely shift B. Tech students to its permanent campus in Kamand. Since its inception the institute has been involved with more than 275 Research and Development (R&D) projects worth more than ₹120 crore. In the past 10 years, the institute has signed Memorandum of Understanding (MoU) with as many as 11 international and 12 national universities.