Chemistry and Materials Earth Sciences and Environment Engineering and Energy Fundamental physics Mathematics and Computer Science All 
Improving multi-threaded scaling of CONQUEST
ARCHER2-eCSE08-10 : Prof David R Bowler (University College London)Subject Area:
Chemistry and Materials Density functional theory (DFT) is a widely used technique for the modelling of materials. It can be used to predict the atomic and electronic structure of materials in areas as diverse as physics, chemistry, earth sciences, and biochemistry. Standard computational approaches to DFT can only be used to model systems of a few hundred atoms, which restricts the type of problem that can be studied. However, the CONQUEST DFT code is designed to model problems with very large numbers of atoms – from several thousand atoms to millions of atoms. This eCSE project was designed to improve the performance of CONQUEST, so that it runs faster and on larger computers, enabling more challenging and interesting problems to be studied. The code is already massively parallel, but this work improves its performance on multi-core computers. Read more...
Improvements in periodic representation of solvated systems with FHI-aims
ARCHER2-eCSE08-03 : Dr Andrew Logsdail (Cardiff University)Subject Area:
Chemistry and Materials Computational modelling can provide invaluable insights into chemical processes at the atomic scale. These insights can help researchers make new discoveries, for example in the search for new sustainable materials or new adsorbents for medicine. Many of the relevant chemical processes occur in liquids close to a solid surface. However, the complexity of the molecular interactions means that atomistic modelling of liquids is a notoriously difficult task, and computational models must balance accuracy with computational cost. FHI-aims is a widely adopted code for quantum chemistry and materials science, and is especially efficient for simulation of solid surfaces. This project enhanced the capability of FHI-aims to simulate solid surfaces within liquids, improving usability and performance, and allowing the closer alignment of computer models with real-life systems. Read more...
Scaling up and coupling adaptive kinetic Monte Carlo with large-scale DFT
ARCHER2-eCSE05-04 : Prof Chris-Kriton Skylaris (University of Southampton)Subject Area:
Chemistry and Materials Diffusion of atoms and ions in solid state materials is essential for the function of products such as batteries, fuel cells and magnetic materials. Understanding atomic and/or ionic diffusion is therefore essential for the design and controlled manufacture of novel materials. However, computational techniques to study and analyse solid state diffusion are limited. The adaptive kinetic Monte Carlo method (aKMC) based on empirical potentials allows for material properties to be calculated efficiently, but it has clear limitations in its accuracy for certain chemical processes. In contrast, Density Functional Theory (DFT) calculations overcome these limitations, but are computationally more expensive. The recent availability of large numbers of cores on ARCHER2 provides an opportunity to combine these two approaches and develop methodologies capable of harnessing in excess of 100,000 cores. This eCSE project developed an interface to combine an aKMC program (ACDC) and a linear-scaling DFT program (ONETEP), making it possible to undertake large-scale aKMC simulations with a higher degree of accuracy than was previously possible. Read more...
Relativistic all-electron orbital-constrained Density Functional Theory to simulate x-ray photoemission and absorption spectroscopy
ARCHER2-eCSE04-03 : Prof Reinhard Maurer (University of Warwick)Subject Area:
Chemistry and Materials X-ray photoemission spectroscopy (XPS) is one of the most important materials characterization techniques that are used in fundamental research and industrial quality control. FHI-aims is a software package for computational molecular and materials science that provides advanced XPS simulation capabilities. It is used to simulate the chemical and physical properties of atoms, molecules, nanostructures, solids, and surfaces. Such simulations allow researchers to discover new materials, which may be stronger, cheaper or more durable than existing materials. FHI-aims can run efficiently on anything from a laptop to a supercomputer with tens of thousands of cores. However, the section of the code used for carrying out core-hole calculations was outdated and inefficient. The work done in this eCSE project has brought that part of the code up to date, so that it is now more efficient, better documented, and easier to maintain. These changes will significantly enhance the simulation of core-level spectroscopy, enabling the simulating of bigger and more detailed systems in future. The changes will also allow a much broader range of researchers to work on these types of simulations, thus ultimately enabling new scientific discoveries. Read more...
Realising a modular data interface to couple quantum mechanical calculators with external data-driven workflows
ARCHER2-eCSE03-10 : Dr Andrew Logsdail (Cardiff University)Subject Area:
Chemistry and Materials Electronic structure calculations are the workhorse of modern computational chemistry, allowing for the prediction of information for a range of vital societal applications, such as drug efficacy, composition of new solar cells, or environmental impact of pollutants. However, the intrinsically complicated nature of electron interactions leads to a great variety of computational chemistry software. Complex interoperation between computer codes can slow the progress of research. To address this, a new applications programming interface, Atomic Simulation Interface (ASI), was developed and then implemented in established electronic structure software packages. This offers a unified and efficient way to export and import large data structures used in electronic structure calculations and for classical molecular dynamics simulations. Read more...
Support for advanced transition state search techniques in CASTEP
ARCHER2-eCSE02-04 : Dr James R Kermode (University of Warwick)Subject Area:
Chemistry and Materials The CASTEP density functional theory code is a UK flagship code, specialised for solid materials, and is heavily used on ARCHER2 (300-400 active users). While support for obtaining the ground-state electronic and atomic configurations is now very good, computing transition states, reaction rates, and exploring free energy barriers with enhanced sampling were relatively poorly supported before this eCSE was completed, despite their importance for a wide range of chemistry and materials science applications. We have implemented two key new features in the CASTEP code to address these issues: (i) support for the widely used nudged elastic band (NEB) transition state search tool, augmented by a state-of-the-art robust optimizer; (ii) an interface to the i-PI universal force engine, which allows CASTEP to be connected efficiently to a range of external codes with enhanced sampling capabilities. The new tools will aid in reconciling experimental observations with atomic-scale behaviour, helping to guide and interpret future experiments. Read more...
Ludwig on ARCHER2: task-based execution
ARCHER2-eCSE01-26 : Prof Davide Marenduzzo (University of Edinburgh)Subject Area:
Chemistry and Materials Computer simulation of fluids - which encompasses both gases and liquids - is important in many contexts. Such computations are the basis of weather and climate forecasts, and many engineering applications such as aerodynamics. At smaller scales, the same ideas can be used to study e.g., blood flow in the body, or to model the behaviour of bacteria and viruses in fluid surroundings. A long-standing collaboration between the Soft Matter Physics Group at The University of Edinburgh and EPCC has developed the Ludwig code for modelling complex fluids. Ludwig can represent a significant range of complexity including solid-fluid interactions, different fluid compositions, and any electric charge carried by the fluid. It can also represent active objects such as simple bacteria. This eCSE project aimed to recast elements of Ludwig to make the code more flexible and therefore able to fully exploit the capabilities of supercomputers. This will allow larger and more complex science cases to be addressed with improved efficiency on ARCHER2. Read more...
Improving the performance of DL_MONTE for large-scale simulations
ARCHER2-eCSE01-19 : Prof Steve Parker (University of Bath)Subject Area:
Chemistry and Materials Monte Carlo molecular simulation (MCMS) entails using random numbers to calculate properties of solids or fluids at the atomic scale. It is the method of choice for studying various physical phenomena of key relevance to technology: common applications include quantifying the amount of a gas which adsorbs to a surface or material; and calculating the atomic-scale properties of fluids and mixtures. There is an insatiable demand for computer simulation to be able to model more complex systems, e.g. systems comprised of more atoms, or more complex molecules. Motivated by this, this project has enabled an open-source MCMS computer program, DL_MONTE, to simulate significantly more complex systems than it could previously. Read more...
Achieving the sustainability and scalability of numeric-atomic-orbital-based linear response and electron-phonon functionality in FHI-aims
ARCHER2-eCSE01-16 : Dr Reinhard Maurer (University of Warwick)Subject Area:
Chemistry and Materials Most calculations run on ARCHER2 will employ electronic structure software packages, which are designed to solve the Schrödinger equation for molecules and materials to obtain their ground state properties. FHI-aims is one such software package, designed to be efficient when running everything from small calculations on standard laptops to huge calculations involving millions of atoms on the largest High Performance Computing systems such as ARCHER2. It is of wide interest to also calculate how molecules and materials respond to atomic displacements, or to electric and magnetic fields. This is possible using density functional perturbation theory (DFPT). A portion of the existing DFPT infrastructure within FHI-aims has been overhauled within this project, to make it more modular, intuitive, scalable, and user and developer friendly. These changes will help researchers to discover and design the next generation of materials more quickly, more cheaply, and more efficiently. Read more...
Zacros Software Package Development: Towards Petascale Kinetic Monte Carlo Simulations with the Time-Warp Algorithm
ARCHER2-eCSE01-13 : Dr Michail Stamatakis (University College London)Subject Area:
Chemistry and Materials The chemical industry underpins virtually all sectors of the economy, from healthcare to construction. Catalytic materials, which accelerate reactions, are essential to this industry. Yet discovering catalytic materials and building catalytic processes is non-trivial. Theory and simulation can guide such efforts by delivering fundamental understanding of catalytic function. Zacros is a computational code that simulates chemical events on catalytic surfaces and enables scientists to understand how catalysts accelerate chemical reactions. This eCSE project investigated how the performance of the code is affected by different user-tuneable parameters that affect the efficiency of the parallel algorithm implemented in Zacros. The most important parameter affecting the efficiency of a run was thus identified, and tools were developed that allow users to optimise it for the systems they would be interested in simulating. The improvements made to the code will facilitate further development of improved algorithms and new features in the future. Read more...
CASTEP Solvation Forces
ARCHER2-eCSE01-09 : Prof Matt Probert (University of York)Subject Area:
Chemistry and Materials Density-functional theory (DFT) is a quantum mechanical modelling method which is widely used in physics, chemistry and materials science to study the properties of materials where electrons dictate their behaviour. CASTEP is a UK flagship code which uses DFT to simulate a wide range of properties of materials, such as structure at the atomic level or the vibrational properties of the material. It is one of the most used codes on ARCHER2. Prior to this eCSE project, CASTEP was well adapted to investigating electronic and atomic configurations in solid materials, but not so well suited to investigating isolated molecules, or molecules in solvent, for which there is a wide range of chemistry and materials science applications. The aim of this eCSE project was to add new functionality to CASTEP to address this shortcoming, building on the work carried out in a previous ARCHER eCSE project. The result enables CASTEP users to accurately simulate molecules in solvent, without the cost of explicit solvent molecules. This will therefore open wider avenues of research with CASTEP, for instance, the study of pharmaceutical compounds and future battery designs. Read more...