Research

Researchers in the Materials and Molecular Modelling (MMM) Hub are carrying out groundbreaking research to better understand the properties of existing and new materials. Some of this work is focussed on developing more energy efficient catalysts, lighter, stronger, smarter materials, improved sensors, batteries, membranes and so on. Work also focusses on better understanding how the material world functions, such as the inner workings of the earth’s core, the formation of ice in the atmosphere, the fracture of rocks, and more.

Why research materials?

Materials have an enormous impact on the UK economy: according to the former Minister of State for Universities and Science, UK businesses that produce and process materials have a turnover of around £170 billion per annum and represent 15% of UK GDP. At the heart of almost every modern technology, including energy generation, storage and supply, transportation, electronic devices, defence and security, healthcare, and the environment, it is materials that place practical limits on efficiency, reliability and cost.

Why materials modelling?

MMM is an inherently interdisciplinary ‘field’ of physicists, chemists, engineers, materials scientists, biologists, geologists, and more who use high performance computing to enable transformative discoveries of importance to science and industry. The predictive capability of MMM has increased significantly in recent years. MMM can provide fundamental insights into the processes and mechanisms that underlie physical phenomena and has become an indispensable element of contemporary materials research.

It is no exaggeration to state that MMM is changing how new materials-based technologies are developed, acting as a guide for experimental research, helping to speed up progress and save resources. It is a rapidly expanding field and one in which the UK has consistently been world-leading.

Case studies

A selection of the top publications, ordered by citations, that were made possible by the MMMHub and Young

Theory and Simulations of Ionic Liquids in Nanoconfinement

Authors: Kondrat, S; Feng, G; Bresme, F; Urbakh, M; Kornyshev, AA | Published: Chem. Rev. (2023)

Molecular simulation visualization of ionic liquids in nanoconfinement

Overview & Motivation

Ionic liquids confined in sub-nanometer pores exhibit extraordinary structural and dynamical behaviors distinct from their bulk counterparts, with major implications for energy storage, supercapacitors, and catalysis.

Methodology & Approach

State-of-the-art molecular dynamics simulations and statistical mechanics theories were deployed to unravel how spatial restrictions alter ion-ion correlations, charge screening, and interfacial capacitance.

Impact

This comprehensive review establishes unified theoretical frameworks for optimizing nanoconfined ionic fluids in next-generation green energy devices.

The ONETEP linear-scaling density functional theory program

Authors: Prentice, JCA et al. | Published: J. Chem. Phys. (2020)

Visualization of linear-scaling density functional theory calculations using ONETEP

Overview & Motivation

Standard density functional theory (DFT) methods scale cubically with system size, severely bottlenecking atomistic simulations of thousands of atoms. Linear-scaling approaches are essential to push quantum mechanics to massive systems.

Methodology & Approach

The ONETEP software development incorporates non-orthogonal generalized Wannier functions (NGWFs), enabling computational effort to scale linearly with the number of electrons while maintaining plane-wave accuracy.

Impact

Provides the materials modelling community with a robust, highly parallelized engine capable of executing first-principles quantum calculations on systems comprising thousands of atoms on high-performance computing architectures.

Structural properties of sub-nanometer metallic clusters

Authors: Baletto, F | Published: J. Phys.-Condes. Matter (2019)

Atomic structure models of sub-nanometer metallic clusters

Overview & Motivation

Sub-nanometer metallic clusters bridge the gap between isolated atoms and extended nanoparticles, exhibiting quantum size effects that drastically alter catalytic activity and stability.

Methodology & Approach

Advanced global optimization algorithms combined with accurate interatomic potentials and density functional theory calculations mapped potential energy surfaces and fluxional isomers.

Impact

Deepens fundamental understanding of nano-alloy structures and design rules for tailor-made nanocatalysts.

Monolayer C60 networks: a first-principles perspective

Authors: Peng, B; Pizzochero, M | Published: Chem. Commun. (2025)

First-principles atomic model of monolayer C60 networks

Overview & Motivation

Two-dimensional fullerene polymers combine molecular building blocks with covalent networks, offering unique electronic, mechanical, and optical tunability.

Methodology & Approach

First-principles density functional theory calculations investigated structural stability, electronic band structures, and mechanical anisotropy of novel monolayer C60 architectures.

Impact

Outlines design principles for synthesizing robust carbon-based 2D materials with tailored optoelectronic properties.

Simulating excited states in metal organic frameworks: from light-absorption to photochemical CO2 reduction

Authors: Ingham, M; Aziz, A; Di Tommaso, D; Crespo-Otero, R | Published: Mater. Adv. (2023)

Simulated charge transfer and excited states in metal-organic frameworks

Overview & Motivation

Metal-organic frameworks (MOFs) hold high promise for artificial photosynthesis and solar-driven carbon dioxide capture and conversion.

Methodology & Approach

Time-dependent density functional theory (TD-DFT) and multiconfigurational approaches mapped light absorption, exciton localization, and photoinduced charge transfer pathways.

Impact

Identifies key mechanistic factors governing photocatalytic efficiency in porous crystalline materials for green energy applications.

Axion global fits with Peccei-Quinn symmetry breaking before inflation using GAMBIT

Authors: Hoof, S; Kahlhoefer, F; Scott, P; Weniger, C; White, MJ | Published: High Energy Phys. (2019)

Global fit parameter space plot for axion dark matter models

Overview & Motivation

Axions are leading candidates for cold dark matter, yet constraining their parameter space requires robust statistical integration across cosmological and particle physics data.

Methodology & Approach

Utilized the GAMBIT (Global and Modular Beyond-the-Standard-Model Inference Tool) framework to perform extensive multi-dimensional parameter scans under early-universe inflation scenarios.

Impact

Delivers rigorous statistical constraints on axion mass ranges and cosmological abundance, guiding ongoing and future experimental searches.

A perspective on the microscopic pressure (stress) tensor: History, current understanding, and future challenges

Authors: Shi, KH; Smith, ER; Santiso, EE; Gubbins, KE | Published: J. Chem. Phys. (2023)

Microscopic stress tensor distribution across inhomogeneous fluid interfaces

Overview & Motivation

The microscopic pressure tensor is fundamental for understanding interfacial thermodynamics, surface tension, and mechanical stability in inhomogeneous systems.

Methodology & Approach

Reviewed historical developments, theoretical ambiguities, and modern computational implementations of local stress definitions in molecular simulations.

Impact

Clarifies longstanding ambiguities in non-uniform fluid mechanics and outlines standardized protocols for stress calculation in complex geometries.

QSGW: Quasiparticle self-consistent GW with ladder diagrams in W

Authors: Cunningham, B; Gruening, M; Pashov, D; van Schilfgaarde, M | Published: Phys. Rev. B (2023)

Electronic band structure calculated via quasiparticle self-consistent GW

Overview & Motivation

Standard electronic structure methods often fail to accurately capture band gaps and excited-state properties in strongly correlated materials due to neglect of vertex corrections.

Methodology & Approach

Implemented quasiparticle self-consistent GW incorporating ladder diagrams in the screened Coulomb interaction ($W$), going beyond standard random-phase approximations.

Impact

Significantly improves predictive accuracy for optical and electronic properties of complex semiconductors and insulators.

In Depth Case study: The Origin of Negative Thermal Expansion in Layered Perovskites

Chris Ablitt, Sarah Craddock, Mark Senn, Arash Mostofi and Nicholas Bristowe

We showed that in a certain layered perovskite oxide, the material shrinks along the layering axis with increasing temperature due to the effects of both soft vibrations of rigid structural units and a high elastic anisotropy, which is a feature specific to the symmetry of this material.

Figure showing a) Structure of the negative thermal expansion material showing the rigid units that vibrate b) proposed model to explain the high elastic anisotropy, where springs represent weak bonds and rods represent stiff bonds that do not need to deform when the material changes shape with temperature.
Figure 1: a) Structure of the negative thermal expansion material showing the rigid units that vibrate b) proposed model to explain the high elastic anisotropy, where springs represent weak bonds and rods represent stiff bonds that do not need to deform when the material changes shape with temperature. Both figures have been taken from the article and may be subject to copyright by the publisher.

Who: Collaboration between experimental crystallography and computational materials modelling groups at several UK universities including Imperial College London, the University of Warwick, the University of Kent and the University of Oxford.

What: Using first principles simulations, we were able to reproduce the negative thermal expansion (NTE) along the layering axis of a layered perovskite material with good agreement with experimental measurements. Analysing the simulations allowed us to identify vibrations of rigid structural units to be the driving force for NTE. However, we also discovered that the structure has a high elastic anisotropy that facilitates NTE and is necessary to explain why the phenomenon arises in this material and not similar materials. We were then able to propose an atomic mechanism to explain why this compliance arises from the symmetry of the material.

When: The article is in Nature Computational Materials, with publication date on 16th October 2017.

Why: Most materials expand when they are heated, but some do the opposite and shrink, a phenomenon known as negative thermal expansion (NTE). When two different materials are paired together in intricate electronic devices, their different expansion rates with changing temperature can be a major source of failure. Perovskites are important technological materials with many applications in bulk and thin film electronics. By understanding the origin of NTE in one of the rare examples of a material within the perovskite family exhibiting the phenomenon, we hope to pave the way to designing new materials with tuneable thermal expansion.

How: Using first-principles simulations we computed the atomic vibrations in structures with different dimensions and used these results to solve thermodynamic equations to predict the equilibrium structure as a function of temperature. We then compared these structures to those measured in a real material using a high-resolution neutron power diffractometer at the ISIS neutron spallation source. A large number of calculations were required over all the different deformed structures to ensure convergence and therefore the computational resources provided by the MMM were essential to the project.

In Depth Case study: Metal-Insulator Transition in Copper Oxides Induced by Apex Displacements

Swagata Acharya, Cédric Weber, Evgeny Plekhanov, Dimitar Pashov, A. Taraphder, and Mark Van Schilfgaarde

LSCO Phase Diagram
Superconducting temperature Tc as a function of the displacements of the apical oxygens in La2CuO4. The optimal temperature correlates with the transition between a metal and insulator: the electrons in this regime have a dual character, they are both itinerant and localized at the same time. The fluctuations stemming from this competition are optimum to generate superconductivity, and the Tc is maximum.

We provide a novel pathway to optimize the superconducting temperature in copper oxide superconductors.

Who: King’s College London lead project (Cedric Weber, Mark Van Schilfgaarde), with international collaboration with the Simons foundation (US) and Prof A Taraphder (India).

What: High-temperature superconductors conduct electricity with zero resistance at temperatures well above absolute zero but below some critical temperature (Tc). Finding a way to push Tc to higher values opens a path to superconductors that operate at more practical temperatures. However, finding a single parameter that can control Tc continues to elude physicists. Here, we show how the bond length between copper and oxygen atoms in copper-oxide-based superconductors can alter the critical temperature.

When: The article is in Physics Review X, with publication date on Dec 11th 2017. See link: https://journals.aps.org/prx/abstract/10.1103/PhysRevX.8.021038

Why: Cutting-edge research on a timely and hot-topic involving key players in the field, which opens a clear pathway to put King’s at the forefront of the research on tailoring functional materials.

How: Timely and novel results on directions to improve Tc in superconductors. This project has led to two direct extensions of the work with high impact: how to control electronic properties with ultra-fast laser pumping, via a joint international collaboration with MIT, EPFL and KCL. This recent extension is about to be submitted to Nature Physics.

In Depth Case study: Aggregation-induced emission in lamellar solids of colloidal perovskite quantum wells

Jakub Jagielski, Sudhir Kumar, Mingchao Wang, Declan Scullion, Robert Lawrence, Yen-Ting Li, Sergii Yakunin, Tian Tian, Maksym V. Kovalenko, Yu-Cheng Chiu, Elton J. G. Santos, Shangchao Lin and Chih-Jen Shih

We created the brightest green colour ever achieved by any nanomaterial up to date.

Photo of the LED before the AIE process takes place.
LED before the AIE process takes place.

Who: International collaboration between several top-notch groups in Switzerland (ETH Zurich, Empa—Swiss Federal Laboratories for Materials Science and Technology), USA (Florida State University), Taiwan (National Taiwan University of Science and Technology, National Synchrotron Radiation Research Centre), and United Kingdom (Queen’s University Belfast).

What: The fluorescent semiconductor nanocrystals have been used in the state-of-the-art optoelectronics, in particular in the ultrahigh definition displays (e.g. iPads). The optoelectronic performance of these compounds is typically proportional to their fluorescence, a process that emits light after absorbing photoenergy. In order to harvest more-light, it is required to find a way to “scale up” and “collect” the fluorescence from individual nanocrystals, while the efficiency is generally low. In this work, we report the first ever semiconductor nanocrystals that enhance their fluorescence after forming an aggregated, ordered structure in a unprecedented way. It will potentially lead to optoelectronics with the highest electricity-to-light efficiency. In other words, brighter, cheaper and more energy-efficient smart devices.

When: The article is in Science Adv., with publication date on Dec 22nd 2017. See link: http://advances.sciencemag.org/content/3/12/eaaq0208

Photo of the LED after the AIE process.
After the AIE process.

Why: Cutting-edge research on a timely and hot-topic involving key players in the field, which opens a clear international pathway to put Queen’s at the road-map of optoelectronic applications.

How: Timely and novel results on the measurement, simulations, explanation and potential applications of this new effect ever observed in any nanomaterial so far. The concept is unique and the findings even more attractive for further investigations and potential applications.