IIT Mandi's Gautam R. Desiraju Honored with Prestigious Ewald Prize

Recognition for Pioneering Work in Crystal Engineering

Professor Emeritus Gautam R. Desiraju from the Indian Institute of Technology (IIT) Mandi has received the esteemed 14th Ewald Prize from the International Union of Crystallography (IUCr). This accolade recognizes his groundbreaking contributions to crystal engineering and his innovative research on molecular interactions that shape the structure and characteristics of crystals.

The award, one of the highest honors in the field of crystallography, was conferred upon Professor Desiraju on August 11 in Calgary, Canada, during the International Congress of Crystallography.

Presented every three years, the Ewald Prize honors exceptional contributions to crystallography. Professor Desiraju was specifically acknowledged for his role in establishing the concept of supramolecular synthons and for highlighting the significance of weak hydrogen and halogen bonds in both molecular crystals and biological systems.

His research has revolutionized crystal engineering, transforming it from a descriptive field into a predictive and design-focused science, with applications spanning pharmaceuticals to advanced functional materials.

In addition to his role at IIT Mandi, Professor Desiraju is also a Professor Emeritus at the Indian Institute of Science in Bengaluru and a Distinguished Professor at IIT Mandi’s IKS MHA. His extensive research has centered on understanding molecular interactions and how they lead to the formation of crystalline structures, enabling the intentional design of materials with specific properties.

Upon receiving the award, Professor Desiraju remarked that the Ewald Prize is considered one of the highest accolades a structural chemist or biologist can achieve, emphasizing the rigorous and confidential selection process involved.

IIT Mandi Director Professor Laxmidhar Behera congratulated Professor Desiraju, stating that this recognition is a significant source of pride for both IIT Mandi and Indian science. He noted that Professor Desiraju’s groundbreaking research has greatly enhanced the understanding of molecular interactions and opened new avenues in pharmaceuticals and advanced materials.

A Journey Driven by Curiosity

Professor Desiraju’s scientific exploration was sparked by a fundamental question: Why do crystals form the structures they do?

While conducting research at the University of Illinois, he found that the prevailing belief was that organic crystal structures were primarily determined by close molecular packing. However, Desiraju began to investigate exceptions—crystals whose structures could not be explained by traditional packing theories.

His focus shifted to weak intermolecular forces, particularly the C—H···O interaction, which was then considered too weak to significantly influence structure. His collaborative research with Thomas Steiner helped establish these interactions as genuine weak hydrogen bonds with crucial structural implications.

Today, such interactions are acknowledged not only in molecular crystals but also in biological systems, where subtle molecular forces can lead to significant functional outcomes.

Transforming Crystal Engineering

One of Professor Desiraju’s most impactful contributions is the concept of the supramolecular synthon, introduced in a pivotal review in 1995.

Drawing inspiration from Nobel laureate E.J. Corey’s retrosynthetic analysis, Desiraju suggested that crystals could be approached similarly to how synthetic chemists view molecules—as entities that can be designed.

The supramolecular synthon concept identifies recurring structural units held together by predictable intermolecular interactions, providing researchers with a framework to anticipate how molecules might assemble into crystals and facilitating the intentional design of crystalline materials.

This approach has evolved from simple binary and ternary co-crystals to increasingly complex multicomponent systems, which Desiraju refers to as the 'Mount Everest of supramolecular solid-state synthesis.'

Real-World Applications in Pharmaceuticals

The significance of crystal engineering is becoming increasingly evident in practical applications, particularly within the pharmaceutical industry.

Pharmaceutical co-crystals can enhance the solubility, stability, and bioavailability of poorly soluble drugs without altering the active pharmaceutical ingredient. Several medications utilizing crystal-engineering techniques have already been introduced to the market.

The field is also tackling major scientific challenges such as polymorphism and crystal structure prediction. Professor Desiraju believes that artificial intelligence could lead to significant advancements in crystal structure prediction within the next five to ten years.

His recent investigations have also delved into mechanically responsive crystals—materials capable of bending, slipping, or returning to their original shape—pointing towards new opportunities in smart and functional materials.

A Leader in Crystallography

Professor Desiraju has authored over 475 research papers, which have collectively garnered more than 80,000 citations. He served as President of the International Union of Crystallography from 2011 to 2014 and continues to be a prominent figure in structural chemistry and crystallography globally.

In conjunction with the Ewald Prize, a special first-person article by Professor Desiraju has been published in the September 2026 issue of the International Union of Crystallography Journal. Titled 'Crystal Clear. Engineering Complexity,' the article chronicles his scientific journey and the evolution of crystal engineering, a field to which he has made foundational contributions.

The article also reflects his broader perspective on crystals as complex, interconnected systems where strong molecular bonds provide stability while weaker interactions offer flexibility and adaptability.

Thus, the Ewald Prize not only acknowledges a distinguished body of research but also recognizes Professor Desiraju’s pivotal role in reshaping how scientists perceive crystals—from mere structures to materials whose properties can be increasingly predicted, engineered, and designed.