At CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), research in crystal engineering and solid-state chemistry is focused on understanding and tuning structure–property relationships in molecular materials. A major thrust involves exploring polymorphism, where distinct crystal forms exhibit unique properties-an aspect of critical physicochemical and intellectual property significance for active pharmaceutical ingredients (APIs). Complementing these fundamental studies, core activities include preformulation and systematic solid-form screening of APIs and excipients to enhance aqueous solubility and dissolution performance, advancing both scientific insight and pharmaceutical applicability. The group also investigates mechanical behavior and anisotropic thermal expansion in molecular crystals, with particular emphasis on flexible crystals that exhibit elastic and plastic deformation and their structural origins, for applications such as optical waveguiding and conductivity.