The Chilton Group

Designing high-temperature single-molecule magnets

The volume of stored digital information is increasing exponentially, and the economic and environmental costs could be mitigated by increasing data densities by orders of magnitude. We design and study lanthanide-based single-molecule magnets (SMMs) with the aim of achieving molecular-scale data storage. By combining electronic structure calculations with synthetic chemistry, we establish structure-property relationships that enable predictive design of magnetic anisotropy and relaxation behaviour. Our work has delivered record-breaking performance, including magnetic hysteresis up to 100 K, representing a major step toward practical molecular memory. Complementary studies demonstrate ultrahard molecular magnetism with coercive fields exceeding 30 T.

• Soft magnetic hysteresis in a dysprosium amide-alkene complex up to 100 K, Nature, 2025
• Ultrahard magnetism from mixed-valence dilanthanide complexes with metal–metal bonding, Science, 2022
• Triangular (C₅ⁱPr₅)₃Ln₃H₃I₂ (Ln = Tb, Dy, Ho, Er, Tm) Clusters with Lanthanide-Dependent Bonding, Valence Delocalization, and Magnetic Anisotropy, J. Am. Chem. Soc., 2026
• Mixed-Valence Aryloxido-Bridged Dilanthanide Complexes with Lanthanide-Dependent Electron Delocalization, J. Am. Chem. Soc., 2025
• Magnetic hysteresis up to 73 K in a dysprosium cyclopentadienyl-amide single-molecule magnet, J. Am. Chem. Soc., 2025
• Coercive Fields Exceeding 30 T in the Mixed-Valence Single-Molecule Magnet (Cp^iPr5)₂Ho₂I₃, J. Am. Chem. Soc., 2024
• Molecular magnetic hysteresis at 60 kelvin in dysprosocenium, Nature, 2017

Spin-phonon and vibronic coupling

We develop first-principles theories of spin dynamics to understand and control spin dynamics in solids and solutions. We have shown that we can accurately calculate spin dyanmics for molecular crystals and fluids, indicating that our techniques have predictive power. We also use experimental techniques such as NMR, EPR, neutron scattering, THz spectroscopy, and a suite of magnetospectroscopies including FIRMS, RAMS and PLUMS. Together, these studies allow us to understand spin dynamics at the atomic level, enabling predictive strategies to suppress decoherence and design better magnetic materials.

• Electron and Nuclear Spin Dynamics of Lanthanide Complexes in Solution, J. Am. Chem. Soc., 2026
• Spin-phonon coupling and magnetic relaxation in single-molecule magnets, Chem. Soc. Rev., 2023
• Soft magnetic hysteresis in a dysprosium amide-alkene complex up to 100 K, Nature, 2025
• Measurement and Analysis of Vibronic Coupling in Two Dysprosium(III) Complexes of Opposite Magnetic Anisotropy, Chem. Eur. J., 2026
• Accurate and efficient spin-phonon coupling and spin dynamics calculations for molecular solids, J. Am. Chem. Soc., 2023
• An analytic linear vibronic coupling method for first-principles spin-dynamics calculations in single-molecule magnets, J. Chem. Theor. Comput., 2022
• Analysis of vibronic coupling in a 4f molecular magnet with FIRMS, Nature Commun., 2022

Molecular qubits for quantum technologies

Of the many potential implementations of quantum bits (qubits), molecular spin qubits are particularly favourable: e.g. they have a low fabrication cost, are perfectly identical and are chemically tuneable. Furthermore, they can be engineered to be robust against magnetic noise and exhibit quantum coherence times rivalling solid state qubits. We design molecular spin qubits and qudits with long coherence times, controllable hyperfine structure, and electric‑field addressability. Recent work demonstrates inverse design strategies and electrically controlled 4f molecular qudits, opening pathways to scalable molecular quantum circuitry.

• Ab Initio Design of Molecular Qubits with Electric Field Control, J. Am. Chem. Soc., 2024
• Modelling Electric Field Control in a 4f Molecular Qudit with Hyperfine Coupling, Commun. Chem., 2026
• Inverse Design of Molecular Qudits for Quantum Circuitry, Inorg. Chem., 2025
• Engineering electronic structure to prolong relaxation times in molecular qubits by minimising orbital angular momentum, Nature Commun., 2019

MRI contrast agents, paramagnetic spectroscopy and solution‑phase structure

Non-invasive bioimaging has revolutionised healthcare, and developing more sensitive and informative probes is paramount for early detection in a wide range of diseases. We use paramagnetic NMR, EPR, and ab initio modelling to determine the structure, dynamics, and coordination geometry of paramagnetic molecules in solution. This work bridges solid‑state and solution magnetism, impacts MRI probe design, and provides new methods for mapping hydration and coordination environments of lanthanide ions.

• Mapping Coordination Number and Coordination Geometry of Lanthanide Ions in Aqueous and Non-Aqueous Solution Phase, J. Am. Chem. Soc., 2026
• Genetically Encoded Pentafluorophenylalanine Enables Quantitative Probing of Local Protein Malleability by ¹⁹F NMR, J. Am. Chem. Soc., 2026
• Approximate Hamiltonians from a Linear Vibronic Coupling Model for Solution-Phase Spin Dynamics, J. Chem. Theor. Comput., 2025
• ³¹P NMR chemical shift anisotropy in paramagnetic lanthanide phosphide complexes, JACS Au, 2025
• Tris-Silanide f-Block Complexes: Insights into Paramagnetic Influence on NMR Chemical Shifts, JACS Au, 2024
• Structural evolution of paramagnetic lanthanide compounds in solution compared to time- and ensemble-average structures, J. Am. Chem. Soc., 2023
• How the Ligand Field in Lanthanide Coordination Complexes Determines Magnetic Susceptibility Anisotropy, Paramagnetic NMR Shift and Relaxation Behaviour, Acc. Chem. Res., 2020
• Lanthanide-induced relaxation anisotropy, Phys. Chem. Chem. Phys., 2018
• Rationalisation of anomalous pseudo-contact shifts and their solvent dependence in a series of C₃-symmetric lanthanide complexes, J. Am. Chem. Soc., 2017

Magnetic exchange coupling and mixed valence

We investigate magnetic exchange, metal–metal bonding, and electron delocalization in lanthanide, transition‑metal, and actinide complexes. Our work has revealed that f-element systems can exhibit strong and tunable exchange interactions, challenging the traditional view of weakly interacting lanthanides. We have demonstrated electron delocalisation in mixed-valence lanthanide complexes with various symmetries, demonstrating how radical bridges can mediate strong exchange coupling. Our work establishes transferable models for exchange interactions and reveals extreme magnetic anisotropy from unconventional bonding motifs.

• Ultrahard magnetism from mixed-valence dilanthanide complexes with metal–metal bonding, Science, 2022
• Taming Super-Reduced Bi₂³⁻ Radicals with Rare Earth Cations, J. Am. Chem. Soc., 2023
• Triangular (C₅ⁱPr₅)₃Ln₃H₃I₂ (Ln = Tb, Dy, Ho, Er, Tm) Clusters with Lanthanide-Dependent Bonding, Valence Delocalization, and Magnetic Anisotropy, J. Am. Chem. Soc., 2026
• Mixed-Valence Aryloxido-Bridged Dilanthanide Complexes with Lanthanide-Dependent Electron Delocalization, J. Am. Chem. Soc., 2025
• δ-Bonding Modulates the Electronic Structure of Formally Divalent nd¹ Rare Earth Arene Complexes, Chem. Sci.
• Strong uranium-phosphorus antiferromagnetic exchange coupling in a crystalline diphosphorus radical trianion actinide complex, Chem., 2025
• Coercive Fields Exceeding 30 T in the Mixed-Valence Single-Molecule Magnet (Cp^iPr5)₂Ho₂I₃, J. Am. Chem. Soc., 2024
• A Trinuclear Gadolinium Cluster with a Three-Center One-Electron Bond and an S = 11 Ground State, J. Am. Chem. Soc., 2023
• Measurement of Magnetic Exchange in Asymmetric Lanthanide Dimetallics: Toward a Transferable Theoretical Framework, J. Am. Chem. Soc., 2018
• Direct measurement of dysprosium(III)···dysprosium(III) interactions in a single-molecule magnet, Nature Commun., 2014

Actinide electronic structure and bonding

We combine spectroscopy and relativistic electronic structure theory to reveal covalency, exchange, and unusual ground states in uranium and transuranic complexes. This work informs fundamental bonding models and functional behaviour in f‑block chemistry.

• Strong uranium-phosphorus antiferromagnetic exchange coupling in a crystalline diphosphorus radical trianion actinide complex, Chem., 2025
• Relativistic Quantum Chemical Investigation of Actinide Covalency Measured by EPR Spectroscopy, J. Am. Chem. Soc., 2024
• Carbene Complexes of Plutonium: Structure, Bonding, and Divergent Reactivity to Lanthanide Analogs, J. Am. Chem. Soc., 2024
• Reactivity of a triamidoamine terminal uranium(VI)-nitride with 3d-transition metal metallocenes, Chem. Commun., 2024
• Investigation of the Electronic Structure and Optical Spectra of Uranium-(IV), -(V) and -(VI) Complexes Using Multi-configurational Methods, J. Phys. Chem. A, 2022
• Anomalous Magnetism of Uranium(IV)-Oxo and -Imido Complexes Reveals Unusual Doubly-Degenerate Electronic Ground States, Chem, 2021
• Rare Earth- and Uranium-Mesoionic Carbenes: A New Class of f-Block Carbene Complex Derived from an N-Heterocyclic Olefin, Angew. Chem. Int. Ed., 2017
• Assessing Crystal Field and Magnetic Interactions in Diuranium-μ-Chalcogenide Triamidoamine Complexes With U^IV-E-U^IV Cores (E = S, Se, Te): Implications for Determining the Presence or Absence of Actinide-Actinide Magnetic Exchange, Chem. Sci., 2017
• Molecular and Electronic Structure of Terminal and Alkali Metal-Capped Uranium(V)-Nitride Complexes, Nature Commun., 2016