Hydrogen Bonding Dynamics in Molecular Systems and Complexes

Hydrogen bonding represents a cornerstone of molecular recognition, assembly and reactivity across chemistry, biology and materials science. Dynamic aspects of hydrogen bonding encompass the continual making and breaking of bonds, proton transfers, and subtle rearrangements in response to environmental changes such as solvent fluctuations, temperature or external fields. These processes occur over timescales spanning femtoseconds to milliseconds and govern phenomena as diverse as enzyme catalysis, transport through biological channels, solvent-mediated conformational switching and the stability of supramolecular architectures. Modern approaches combine ultrafast spectroscopies, advanced nuclear magnetic resonance techniques, high-level quantum chemical calculations and molecular dynamics simulations to characterise bond lifetimes, free-energy landscapes and the cooperative interplay among multiple hydrogen bonds. Understanding these dynamics underpins the rational design of functional materials, precision drug discovery and insight into fundamental processes such as proton conduction in fuel cells.

Research from Nature Portfolio

Recent investigations have demonstrated that the two nuclear-spin isomers of water, known as para- and ortho-water, display distinct reactivities in prototypical ion–molecule interactions. By separating pure beams of each isomer and reacting them with diazenylium ions, researchers have shown that differences in rotational motion lead to measurable variations in capture rates and product distributions, highlighting how subtle changes in hydrogen-bond orientation and ion–dipole alignment influence reaction dynamics.

Time-resolved studies using seeded free-electron lasers have begun to map the earliest steps of hydrogen-bond rearrangement in prototypical systems such as acetylacetone. With femtosecond resolution, these experiments resolve transient states in which intramolecular hydrogen bonds strengthen or weaken following photoexcitation, offering a direct view of energy redistribution pathways and the coupling between electronic and geometric changes that drive subsequent fragmentation or relaxation.

Hydrogen Bonding Dynamics in Molecular Systems and Complexes publication trend

The graph below shows the total number of articles in hydrogen bonding dynamics in molecular systems and complexes across all publications each year (not limited to Nature Index journals).

Technical terms

Hydrogen bond: A directional, noncovalent attraction between a hydrogen donor (X–H) and an electronegative acceptor (Y) bearing a lone pair, essential for molecular recognition and structure.

Hydrogen-bond dynamics: The temporal evolution of hydrogen-bond formation, breakage and rearrangement, often characterised by lifetimes, exchange rates and energy barriers.

Quantum theory of atoms in molecules (QTAIM): A framework analysing the topology of electron density to identify bond critical points and characterise noncovalent interactions.

Source function: A method that partitions the total electron density at a point into contributions from individual atoms, used to gauge localisation or delocalisation in bonding.

Resonance-assisted hydrogen bond: A hydrogen bond whose strength is increased by π-electron delocalisation in a conjugated system.

Ultrafast spectroscopy: Experimental techniques employing femtosecond to picosecond pulses to probe rapid structural and electronic dynamics in molecular systems.

Nuclear-spin isomers: Distinct forms of a molecule differing only in the spin alignment of their nuclei, which can influence rotational states and intermolecular interactions.

References

1. Observation of different reactivities of para and ortho-water towards trapped diazenylium ions. Nature Communications (2018).
2. Acetylacetone photodynamics at a seeded free-electron laser. Nature Communications (2018).
3. Exploring the Non-Covalent Bonding in Water Clusters. International Journal of Molecular Sciences (2023).
4. Revealing the Reasons for Degeneration of Resonance-Assisted Hydrogen Bond on the Aromatic Platform: Calculations of Ortho-, Meta-, Para-Disubstituted Benzenes, and (Z)-(E)-Olefins. Molecules (2023).