Isomerism in Energetic Materials: Where Structure Defines Performance

Abstract

Isomerism has long been regarded as a minor structural variation in energetic materials, as isomeric compounds often display nearly identical theoretical detonation parameters. However, recent experimental and theoretical studies have overturned this assumption, revealing that stereoisomerism, regiochemistry, and positional isomerism can exert a profound influence on key physicochemical properties, including melting behaviour, density, thermal stability, sensitivity, and processability. These isomer-dependent effects govern real-world performance and applicability directly, often outweighing marginal differences in energetic output. This review provides the first comprehensive and systematic analysis of isomerism in energetic materials, encompassing reported stereoisomers and regio-/positional isomers across a broad range of energetic frameworks. Emphasis is placed on structure–property relationships, synthetic strategies, and the underlying roles of crystal packing and intermolecular interactions. By consolidating previously dispersed literature and highlighting isomerism as a powerful yet underutilized design parameter, this review establishes molecular isomerism as a fundamental concept for the rational development of safer, tunable, and application-driven energetic materials.