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Annual Report for EPSRC High End Computing Consortia

Reporting Period: February 2015 - January 2016

HEC Consortia: Materials Chemistry

Consortia Chair/Manager: Richard Catlow / Scott Woodley

Allocation and Usage profiles during the reporting period EPSRC to complete when template has been submitted.

Summary (max. 2 pages):

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Background The Materials Chemistry Consortium (MCC) covers the modelling and prediction of the structures, properties and reactivities of materials. The emphasis is on modelling at the atomic and molecular level but with links to models at larger length and time scales. The current scientific programme embraces seven related themes: catalysis, energy storage and generation, surface and interfacial phenomena, nano- and defect structures, soft matter, biomaterials, environmental materials. The MCC has an active programme of code development and optimisation, supported by the SLA and EPSRC software initiatives. A wide range of techniques is used: both force-field methods employing static and dynamical simulation methodologies and electronic structure methods with a strong emphasis on Density Functional Theory (DFT) techniques using both periodic boundary condition and embedded cluster implementations.

Highlights for the Current Reporting Period The scientific output of the consortium remains consistently high in both volume and quality, with over 140 publications during the last reporting period. Recent highlights, discussed in greater detail below include:

In the theme of Energy Storage, modelling of the energy band alignment of the eight known polymorphs of TiO2 explains a diverse range of key phenomena from water-splitting efficiencies to transparent conducting oxide performance [Buckeridge et al., Chem. Mater., 27, 3844, 2015].

In Energy Generation work on hybrid solar cell materials based on organic-inorganic halide perovskites has explained the unusual transport behaviour, such as current-voltage hysteresis which was shown to be linked to ion transport [Eames et al., Nature Commun., 6, 7497, 2015].

In Nano and Defect Structures, modelling in synergy with high level experiment has elucidated the origin of the band gap renormalisation in transparent conducting oxides [Scanlon et al., Phys. Rev. Lett., 116, 027602, 2016].

In Surfaces and Interfaces, very significant progress has been made in the area ice nucleation [Cox et al., J. Am. Chem. Soc., 137, 13658, 2015], by exploitation of the power of ARCHER in long timescale brute-force molecular dynamics to probe ice nucleation from liquid water.

In Soft Matter, substantial advances have been made in the study of charge transfer in organic and biological molecules and in the creation of databases for the calculation of electronic coupling matrix elements for electron transfer in organic donor-acceptor systems [Kubas, et al., Phys. Chem. Chem. Phys., 17, 14342, 2015].

Workshops and New Opportunities The consortium has held three full one-day consortium meetings during then last year [19th February 2015, 6th July 2015, 21st January 2016, and an interim call November 2015]. Additional events during 2015 included:

A workshop held at UCL (October 21st) to coordinate work in the consortium on actinide oxides, attended by groups from UCL, Cardiff, Bath and Manchester. This useful and successful meeting will be held again ion 2016

A workshop in collaboration with PNNL, held at UCL and including staff from Daresbury (November 16th – 18th) to coordinate and develop further collaboration relating to the CHEMSHELL code.

Plans for 2016 , in addition to our regular consortium meetings, include:

A workshop at Daresbury (20th – 22nd January) on periodic electronic structure codes, organised by the Daresbury team in collaboration with MCC and UKCP. The workshop will aim to ensure that consortium members use these codes in the optimum and most efficient manner appropriate for particular applications.

A three day conference on Applications of HPC in Materials Chemistry to be held in Cardiff (April 6th -8th) which will focus on the latest scientific advances in the field and which will include both consortium members and industrial and international participants as speakers. The meeting will also include speakers and participants from UKCP.

Issues and Problems Although the management of the consortium is proceeding well, the lack of staff resource, which for consortium management is only 0.5 FTE, raises problems and means that, for example, we are unable to allocate further effort to web-site development and are limited in our ability to undertake outreach and

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training activities. The project, however, receives good support from the Daresbury SLA support team for software development and maintenance. The consortium has allocated and used its time effectively, with a good turnover and throughput. Importantly, the consortium has a very careful procedure for allocating time: proposals from MCC members are peer reviewed and discussed at meetings; proposers of large projects that requested >10M AU are required to submit reports; most of the larger projects are regularly presented to the general meetings; authors of projects from overlapping themes are encouraged to collaborate and/or run ad hoc workshops and seminars; the best choice of software is monitored and experts are invited to guide and advise; and previous time usage, and especially under-usage, are carefully checked and considered in the concurrent and subsequent time allocations). However, the change of the mode to six-month allocations does present additional time management and book-keeping challenges. Even though we distribute time over more than 150 budget codes, from our time usage one can see that the target spending rate was achieved quite successfully until we approached the hard time allocation boundary. In the past we would over-allocate (based on an estimate of a predicted total under-spend of supported projects for the upcoming period) and not rely on a practice of adjusting time quotas on the-fly as the six-month period comes to the close. The over-allocating policy was previously possible as time for the entire grant was held in reserve and could be allocated, thus providing for the required flexibility. Moreover, information of under-spent budgets could be retrieved on SAFE if required at our meetings. The current policy imposes much harder demands on the time management by the Consortium Manager and the Executive Committee, who need now at very short notice to peer review projects that require time redistribution near the period end. Also, after redistributing time from under-spent projects, SAFE no longer reports these as projects that were under-spent, thus requiring more bookkeeping by the Consortium Management. We would recommend that an additional small percentage is added to a consortium’s reserve that could be allocated to its members near the end of a period, but with the condition that all jobs would end once the expected usage of that consortium had been exceeded; such a procedure would help us manage budgets. The response of ARCHER in the interactive mode (on the command line on the head nodes) is often sluggish and sometimes frustratingly slow. As reported previously at HEC consortia meetings, the response time of SAFE is far too slow for the chosen method of allocating time and members to groups. We strongly recommend that this procedure is changed as each budget allocation is currently required to be entered individually, which is followed by a response delay of typically one minute before the next budget can be entered; likewise for allocating members to groups. The solution is straightforward, i.e. a text box and a radio button per budget code so that the increased size of allocation can be entered for as many budgets as the user chooses (radio button indicates from which budget the time is taken from). One can still have the current safe guards of being able to submit many times and then being able to click “commit changes” once the user is happy all is well.

Membership The consortium is a large but coherent grouping with over 300 registered users on ARCHER from over 60 research teams based in 22 universities. Since January 2015 five new investigators [Johannes Lischner (Imperial College); Nikolas Kaltsoyannis (Manchester); Alberto Striolo (UCL); Matthew Watkins (Lincoln); Marc-Oliver Coppens (UCL)] have joined the consortium and the consortium continues its policy of admitting new members [currently considering applications from Michail Stamatakis (UCL); Michelle Moram (Imperial); Saurav Goel (Queens, NI); Denis Kramer (Southampton); Paul Mulheran (Strathclyde); Jin-Chong Tan (Oxford); and Stanko Tomic (Salford)] provided the science proposed is within the remit of the consortium and is of high quality.

World class and world leading scientific output: ARCHER should enable high quality and world-

leading science to be delivered. This should generate high impact outputs and outcomes that increase the UK’s position in world science.

All themes within the consortium continue to be highly productive with outputs in world leading journals. Recent achievements in each of themes are now summarised:

Energy Storage (Theme Leader: Saiful Islam) In line with the original proposal there has been substantial progress in the computer simulation of atomic,

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transport and electronic processes of materials for energy storage using the ARCHER facilities. Materials performance lies at the heart of the development and optimisation of energy storage devices. An example of an important challenge is increasing the energy density and charge rate of lithium-ion batteries – vital factors for battery use in next-generation portable electronics and hybrid/electric vehicles. The breadth of the computational work is evident from the following selection of scientific highlights:

Solid electrolytes that are stable and have a high ionic conductivity would dramatically enhance the safety and operating lifespan of lithium batteries. MD simulations combined with impedance and NMR studies of the Li-ion conducting system (1-z)Li4SiO4–(z)Li3PO4 show orders of magnitude higher conductivities in the mixed compositions than in the parent phases (Li4SiO4 and Li3PO4). The MD results reveal new mechanistic insights in which fast Li ion conduction occurs through 3D pathways and a cooperative interstitial mechanism [Deng et al., J. Am. Chem. Soc., 137, 9136, 2015].

A combined hybrid eigenvector following and DFT based approach was developed and used to investigate the complex potential energy landscape associated with the ionic and electronic diffusion in the layered oxide cathode LixMnO2. This single-ended searching method should prove useful for studying the phase transformation mechanisms and diffusional properties of a wide range of technologically interesting energy materials. [Leuan et al, Chem. Mater, 27, 16, 2015].

Potential aliovalent dopants to introduce Li ion vacancies in the olivine LiMgPO4 were screened using DFT methods, and substitution of In by Mg identified as the preferred doping strategy. Subsequent experimental synthesis showed that the introduction of Li ion vacancies by doping was indeed possible and showed over 100 times faster Li ion conductivity at room temperature [Enciso-Maldonado et al., Chem. Mater., 27, 2074, 2015].

Energy Generation (Theme Leader: Nic Harrison) This theme is developing exciting new science in several key current topics, including the following:

The development of efficient and flexible hybrid solar cells based on organic-inorganic halide perovskites has stimulated a wide range of studies of the material properties. A particular highlight is the explanation of unusual transport behaviour, such as current-voltage hysteresis which was thought to be linked to ion transport. This has been examined in first principles calculation of ion migration in methylammonium lead iodide (CH3NH3PbI3) which is found to be in close agreement with kinetic data extracted from the measured current-voltage response. As noted above, this finding suggests facile vacancy-assisted migration of iodide ions and that hybrid perovskites are mixed ionic-electronic conductors [Eames et al., Nature Commun., 6, 7497, 2015].

There has also been significant progress in the identification of new cheap, flexible and processable materials for high efficiency electronic devices. For example, large scale simulations of self-assembled organic monolayers based on recent extensions of density functional theory have been instrumental in establishing the viability of novel magneto-electronic devices based on transition metal phthalocyanines [Serri et al., Nature Commun., 5, 3079, 2014].

As noted earlier, the energy band alignment of the eight known polymorphs of TiO2 was determined using electronic structure calculations via an embedded cluster approach. The resulting alignment, showing a surprising variation in valence band position as a function of local structure, helped explain a diverse range of phenomena from water-splitting efficiencies to transparent conducting oxide performance [Buckeridge et al., Chem. Mater., 27, 3844, 2015].

Surface and Interfacial Phenomena (Theme Leader: Ben Slater) There has been strong output from the surfaces and interfaces theme over the last 12 months spanning a very broad range of topics, from the fundamental, to highly applied studies.

On the fundamental side, one example of very significant progress is in the area ice nucleation [Cox et al., J. Am. Chem. Soc., 137 13658, 2015]. Long timescale brute-force molecular dynamics simulations showed that contrary to expectation, the interaction strength between water and the substrate has a complex interplay. In figure 1, the nucleation enhancement rate is shown on the vertical axis and the strength of interaction on the horizontal axis. When the interaction energy between water and the substrate is around half the liquid water heat of vaporisation, nucleation is maximised. When the interaction strength exceeds half the liquid water heat of vaporisation, a different structuring between water and the interface occurs which slows nucleation. By blocking particular surface sites, the green point the figure below, nucleation can be increased beyond the limit possible for a pristine surface.

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Another rapidly developing topic is the use of hybrid DFT calculations to probe the electronic

structure of a thermoresponsive MOF, MIL-53 (pubs.acs.org/doi/abs/10.1021/acs.jpcc.5b04050). The density of MIL-53 halves as the structure is heated from 150K to just over room temperature. What is surprising is that the band gap changes by ~1eV with this density change, a sensitivity which is far greater that which is typically observed within semiconducting inorganic solids. This work showed that guests, external pressure and temperature can be used to tailor the band gap for applications such as light induced switching. Unpublished work by collaborators in France (C. Serre et al.) report observed changes in the UV absorption spectra which are in accord with the predictions from hybrid DFT.

Catalysis (Theme Leader: Dave Willock) Modelling is used in an increasingly predictive manner in catalytic science as shown by the following recent studies from within the consortium:

The use of HPC resources have enhanced our understanding of the properties of the metal nanoparticles that are widely used in catalysis. Johnston and co-workers [Jennings et al, J. Phys. Chem. C, 119, 11031, 2015] have shown how the core/shell structure of mixed Pt/metal particles leads to increased flexibility of the Pt atoms in the outer shell layer. This behaviour leads in turn to a higher activity for oxygen dissociation than for the equivalent pure Pt particles. The reactivity theme has also seen work on the effects of binding of Au atoms and nanoparticles to carbon support materials. In a joint experimental/computational research programme Davies and Willock [Davies et al., J. Catal., 323, 10, 2015] have been able to identify the functional groups introduced during the acid washing step of support preparations and explain how these stabilise the deposited Au nanoparticles. The computational speed of HPC allowed the calculated data to be at a high enough level of theory to inform experimental interpretation with turnaround times that kept pace with the experimental surface science work.

It is now also possible to model the excited state potential energy surface of solvated clusters of important photocatalytic materials such as TiO2. Berardo and Zwijnenburg [E. Berardo et al., J. Phys. Chem. C, 119, 13384, 2015] have used time-dependent DFT to consider water splitting at fully solvated TiO2 nanoparticle models highlighting important cluster size effects in this reaction that could be crucial to the realisation of a hydrogen economy.

Nano and Defect Structures (Theme Leader: Alex Shluger) The consortium members have studied a wide range of defect phenomena in complex oxides, nano-systems and at interfaces. The calculations have predicted, for example, the activation energy barriers for molecular hydrogen and nitrogen dissociation on the surface of Co3Mo3N. They examined the electronic structure and bonding in Sb2S3 and Sb2Se3, and investigated their defect chemistry. They also shed light on the effects of co-doping on the electrical conductivity of SnO2 (F co-doping with Sb, Ta, Nb, and W as the cationic dopant) and in TiO2. In particular, intrinsic trapping properties of interfaces in (210) rutile TiO2 grain boundary have been

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considered with a number of dopant species representing different strategies for passivating deep traps at interfaces. Two-temperature molecular dynamics simulations have been performed to investigate the role of electronic excitation on the structural evolution of W and Si. The electronic structure of high entropy alloys has been examined in detail to understand what shifts the stability of the cell towards body-centred cubic or face-centred cubic configurations. Recently published highlights include:

Origin of High Mobility in Molybdenum-Doped Indium Oxide. The basis for this very unusual behaviour has been investigated by combining density functional theory calculations using a hybrid Hamiltonian and mobility modelling with X-ray photoemission, and X-ray absorption spectroscopies. In contrast to previous claims that Mo acts as a three-electron donor, it is shown that substitutional Mo traps two electrons in localized states falling within the bulk bandgap and thus Mo is a simple one-electron donor [D. S. Bhachu et al., Chem. Mater., 27, 2788, 2015].

Self-Regulation Mechanism for Charged Point Defects in Hybrid Halide Perovskites. Hybrid halide perovskites such as methylammonium lead iodide (CH3NH3PbI3) exhibit unusually low free-carrier concentrations. Quantum mechanical calculations demonstrate that an origin of this phenomenon is a prevalence of ionic over electronic disorder in stoichiometric materials. Schottky defect formation provides a mechanism to self-regulate the concentration of charge carriers through ionic compensation of charged point defects [A. Walsh, et al. Ang. Chemie Int. Ed., 54, 1791, 2015].

Hydrogen-Induced Rupture of Strained Si-O Bonds in Amorphous Silicon Dioxide. Reactivity of atomic hydrogen in amorphous SiO2 was studied using DFT to demonstrate that H atoms can break strained Si-O bonds in continuous amorphous silicon dioxide (a-SiO2) networks, resulting in a new defect consisting of a threefold-coordinated Si atom with an unpaired electron facing a hydroxyl group, adding to the density of dangling bond defects, such as E' centres [ A.-M. El-Sayed, et al., Phys. Rev. Lett., 114, 115503, 2015].

Compressive straining of bilayer phosphorene leads to extraordinary electron mobility at a new conduction band edge. Hybrid DFT calculations predicted that bilayer phosphorene under slight compression perpendicular to its surface exhibits extraordinary room temperature electron mobility [H. M. Morgan et al., Nano Lett., 15, 2006, 2015].

Atomic-scale structure and properties of highly stable antiphase boundary defects in Fe3O4. A combination of predictive first principles modelling with high-resolution transmission electron microscopy was used to unambiguously determine the three-dimensional structure of antiphase boundary defects in magnetite. These defects on the {110} planes are unusually stable and induce antiferromagnetic coupling between adjacent domains providing an explanation for the magnetoresistance and reduced spin polarization often observed [K. P. McKenna, et al., Nature Comm., 5, 5740, 2014].

Environmental Materials (Theme Leader: John Harding) The focus of the environmental theme in the past year has been on simulations for the removal of pollutants from the environment and waste disposal (mainly high level nuclear waste). Notable advances include the following:

Duffy’s group has used molecular dynamics to explain the effects of composition on the diffusion of cations in alkali-alkaline earth silicate glasses for nuclear waste disposal. They find a correlation between the diffusion activation energy and the relative sizes of the ions. Such information is needed to design glasses that are resistant to segregation of ions when used as hosts for waste disposal. [Konstantinou, et al., J. Non-Crystalline Solids, 422, 57, 2015]

Simulations by Parker have investigated layered silicates, which are valuable for environmental and technological applications such as catalysts and adsorbents. The work shows how the edge surface structure and composition affects water transport and adsorption at the mineral interface. These detailed atomistic models will allow us to develop more reliable descriptions of the physio-chemical properties of the edge surfaces and their interaction with contaminants and pollutants in the environment. [Martins et al., J. Phys. Chem., 118, 27308, 2014]

Dove is developing large scale simulations to understand CO2 absorption and release in porous metal-organic zeolitic frameworks (such as zinc imidazolate) using large-scale molecular dynamics techniques. The conditions of the simulations are set to be as close as possible to those expected in real industrial plants.

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Biomaterials (Theme Leader: Jamieson Christie) The biomaterials theme encompasses a very broad range of topics including biomineralisation (PIs: Harding, Freeman, de Leeuw), biological membrane materials (Dove, Parker), electron transfer in biologically relevant systems (Blumberger), biomaterials for implantation (Christie, de Leeuw), proteins in confined environments (Coppens), among others. Two recent developments deserve special note:

Harding and co-workers have studied the effect of chemical connectivity and acidity on the adsorption of a number of oligosaccharides at flat, stepped, and kinked calcite surfaces, to show that the observed reduction in the growth rate of calcite crystals in the presence of these molecules is due to the blocking of high energy sites [Hall et al., Cryst. Grow. Des. – in press].

Christie’s team have used ab initio and classical molecular dynamics to study the atomic structure of Mg-Zn-Ca metallic glass, which has recently been proposed as a biomaterial for orthopaedic implantation. By combining accurate simulation with neutron diffraction, composition-dependent trends in the zinc-zinc and zinc-calcium bonding have been identified, and these correspond with the experimentally determined behaviour [ Christie et al, Phys. Chem. Chem. Phys., 12, 17894 (2015); Gulenko, et al., Acta Mater. – in press].

Soft Matter (Theme Leader: Graham Day) The Organic and Soft Matter theme aims to develop our fundamental understanding, as well as the predictability of, the self-assembly and phase behaviour of soft matter systems. The theme has developed well in the following areas:

As well as traditional areas of soft matter, the theme encompasses research into organic molecular materials, to improve methods for structure prediction [Hasell, et al., J. Am. Chem. Soc., 136, 1438, 2014], investigate crystal nucleation and growth, [Di Tomasso, at al., J. Phys. Chem. A , 118, 11098, 2014], and to evaluate properties of molecular organic systems. The theme has grown in terms of the number of active research groups since it was introduced to the consortium. The breadth of research covered by this theme is a considerable strength, especially as it makes use of a range of software that is available on ARCHER, including force field and ab initio molecular dynamics and density functional theory codes for energy and lattice dynamics calculations. Strong, internationally leading research continues in the area of molecular crystals, benefitting from the capability on ARCHER to evaluate the stability of many potential structures using periodic electronic structure calculations, as well as using density functional theory to model aggregates of molecules in solution. Recently, research has been initiated to investigate the influence of organic component of metal-organic frameworks on their structure and function via large scale ab initio molecular dynamics.

An aim in the past year has been to develop new activity using large scale, coarse grain and atomistic molecular dynamics simulations of the self-assembly of surfactants and polymer aggregates, making use of ARCHER to investigate very large systems over the long timescales required to understand their behaviour. The theme has also supported successful research into change transfer in organic and biological molecules, allowing dynamical simulations and creating databases for the calculation of electronic coupling matrix elements for electron transfer in organic donor-acceptor systems [Kubas, et al., J. Chem. Phys., 140, 104105, 2014; Kubas et al., Phys. Chem. Chem. Phys., 17, 14342, 2015].

PUBLICITY The work of the consortium has received extensive publicity. Examples include:

The work on Gallium Nitride [Phys. Rev. Lett., 114, 016405] which made extensive use of ARCHER resources was highlighted in Scientific American, Chemistry World, Materials World and Materials Today. Links to the articles can be found on http://davidscanlon.com/?page_id=14

The studies referred to earlier on ion diffusion in perovskite hybrid solar cells were highlighted in http://phys.org/news/2015-08-solar-cells.html

Work published in JACS on ice formation [J. Am. Chem. Soc., 137, 13658, 2015] was highlighted as a JACS spotlight

Work on “Electronic structure of porphyrin-based metal–organic frameworks and their suitability for solar fuel production photocatalysis” [J. Mater. Chem. A, 3, 23458, 2015] was commented on in several online news articles: Physorg (UK): http://phys.org/news/2015-10-material-nature-fuel.html; Discovery News (US): http://news.discovery.com/tech/alternative-power-sources/material-splits-

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water-molecule-to-make-fuel-151021.htm; International Business Time (Australian Edition) http://www.ibtimes.com.au/scientists-design-material-can-turn-water-fuel-1476940

Studies of CO2 conversion of iron sulphides [Chem. Comm., 51, 7501, 2015 ] which has relevance to origin of life theories was very extensively highlighted in the media.

LEADING SCIENTIFIC OUTPUTS The summary above has given several examples of world leading science from which it is difficult to select five. However, the five outputs highlighted in the Introduction are representative of the range and quality of the scientific output:

Buckeridge et al., Chem. Mater., 27, 3844, (2015)

Eames et al., Nature Commun., 6, 7497, (2015)

Scanlon et al., Phys Rev Lett, 116, 027602, 2016

Cox et al., J. Am. Chem. Soc., 137 13658, (2015)

Kubas, et al., Phys. Chem. Chem. Phys., 17, 14342, (2015)

Greater scientific productivity: As well as speed increases, the optimisation of codes for

the ARCHER machine will enable problems to be solved in less time using fewer compute resources.

The consortium is actively involved in software development and optimisation, with support from three main sources:

Direct EPSRC supported HEC Software Development A project “Scalable Quantum Chemistry with Flexible Embedding Stage 2” funded by EPSRC as part of the Software for the Future II call, has been carried out in collaboration between two teams one in UCL, Chemistry (Catlow and Sokol) and STFC Daresbury (Sherwood and Keal). The aim of the project is to develop a new Python based implementation of flexible hybrid QM/MM methodologies that will both provide a modern replacement for older technologies employed in the current version of ChemShell, but also allow for a more powerful and easier extendible development in this rapidly developing field. The new package is intended for applications in the field of heterogeneous catalysis, where for the first time it will become possible to simulate reactions on active sites at the interface between nanoparticles supported on metal oxides and liquid solvents, at the high level of chemical accuracy. The work is complemented by the development of new methodologies with the support for spin polarised pseudopotentials (modelling cations in transition metal oxides) and density embedding (to represent solvent molecules). Three groups within the MCC are currently involved in the project and we estimate that 7% of e05 total time expenditure was consumed by ChemShell simulations.

eCSE supported HEC Software Development Project eCSE01-18 (PI Woodley, UCL and Blum, Duke) was completed by M. Farrow in the early Summer 2015 and resulted in a highly optimised tuned version of the FHI-Aims software package, which has been made available to all licensed ARCHER users and outside across the world to the FHI-Aims user community. The primary goal in this project has been to find an alternative hybrid DFT driver to the VASP code which consumes on ARCHER more than 50% of our time allocation. In the MCC strategy this situation is considered as a risk and therefore a number of activities including the current MCC sponsored workshop in Daresbury (Jan 2016) and the push for further development of CP2K are being undertaken. Further eCSE support will be sought in the near future so that this target can be attained. Project eCSE06-7: further support has been sought for the KLMC package (Woodley), which targets massive task farming automation and data management on ARCHER for the problems of structure prediction, statistical sampling and systematic exploration of complex energy landscapes. The initial technical assessment made us aware that our definition of a “client-server” approach was different from that used in other communities. This matter will be clarified and we plan to resubmit in the next call first as the targeted algorithms/ software solutions are important and secondly because ARCHER usage for structure prediction applications are already over 5% of the MCC time allocation, which is anticipated to increase.

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Further eCSE support to members of the MCC includes eCSE06-6 and eCSE03-11 (CP2k) and eCSE04-16 (CRYSTAL).

SLA support which has focussed on three key codes which are widely used by consortium members, namely CRYSTAL, CHEMSHELL and DL_POLY. For CRYSTAL, a large component of the work undertaken has been devoted to the development and optimisation of excited state capabilities and of ab initio molecular dynamics in CRYSTAL. An eCSE proposal submitted for developments in CRYSTAL have been funded for 9 months and Barry Searle has appointed starting 1st September 2015. Good progress continues to be made on the rewrite of CHEMSHELL as a python-based open source code which is accelerated through support from the MCC towards additional features beyond the scope of the original grant and with a strong collaboration with the UCL group. Most of the efforts on the DL_POLY project have been invested in training, outreach and dissemination. However, progress has been made on the software side by pushing a number of parallel development lines, particularly relating to enhancement of functionality relating to meta-dynamics and multipole electrostatics.

Other projects include: In collaboration with Prof. Latour, Chris Lorenz has implemented algorithms into the classical MD code LAMMPS, that will allow for interfacial phenomena to be studied using an approach similar to that used by Latour's interfacial force field. This will be released as the part of an upcoming release of LAMMPS and be available to the general user base of LAMMPS and will be of particular use for simulating biological molecules interacting with non-biological interfaces. Lev Kantorovich and Chris Lorenz have implemented their Generalised Langevin Equation based thermostats into the LAMMPS molecular dynamics simulation package. Currently finalising this implementation, this will initially be distributed from their local websites until beta-testing completed, after which it will be distributed to the general user base. This will be useful when modelling heat transfer.

Increasing the UK’s CSE skills base (including graduate and post doctorate training and support): Training activities include

Consortium meetings which always include items on software development and allow users to share and discuss best practice. MCC members and their teams are targeted; typically over 120 people attend our meetings.

Consortium members are actively encouraged to attend workshops and training events organised by EPCC and STFC RAL and Daresbury. In particular, the periodic DFT workshop (Jan 2016).

It is also worth noting that several students trained by the consortium in applications of HPC techniques in Materials Chemistry have been recruited by Universities and Industry. Recent examples of the latter include Crispin Cooper (UCL, now working in the modelling team at Johnson Matthey) and Nick Brincat (Bath, now working as a research scientists with AWE).

Increased impact and collaboration with industry: The consortium has active collaborations with industry including Johnson Matthey, BP, AWE, IBM, GSK, Perkin-Elmer, Astra-Zeneca, Dyesol, Sellafield and Sematech and the consortium strongly encourages industrial participation and collaboration. Several of the graduate students work on collaborative projects with industry via CASE awards or IDC funded studentships. Current joint projects with industry include:

Modelling of catalytic oxides (UCL/Johnson Matthey) – supported by CASE award and see attached case study.

Modelling of de-NOx catalysts (UCL/JM) – supported by CASE award

Determining Dynamics in Sweet/Sour Corrosion Scales (Imperial/BP) – supported by grant from BP

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funding two theory PDRAs and one expt. PDRA in addition to students

Modelling of acid sites in zeolite catalysts (UCL/BP) – supported by CASE award

Modelling of Crystal Growth of pharmaceutical compounds (QMUL/Astra-Zeneca)- supported by Royal Society Industrial fellowship

Modelling of plutonium dioxide (UCL/AWE) – supported by sponsored CDT studentship

Modelling of actinide oxides (Manchester/Sellafield Ltd) – supported by grant

Consortium members have also been active in conference and workshop organisation which disseminates the work of the consortium to industrial users. Examples include:

Harding (leader of the environment theme) organised and impact workshop on “What can we learn about controlling the crystallisation, self-assembly and properties of materials from biological systems?” (Sept 15-16 at Sheffield) with industrial participation (BACG, Unilever) and which highlighted modelling work supported by the consortium.

Woodley (consortium manager) and Di Tommaso organised the BACG annual meeting at QMUL (21st-23rd June) where half of the participants were industrial scientists.

Catlow (consortium PI) co-organised the workshop on "CO2 conversion and utilisation" (Varadero, Cuba, 24 - 28th June, 2015) which included contributions on the role of HEC based modelling in the field.

Publications including industrial collaborators include:

Shell model force-field for lead zirconate titanate, Pb(Zr1-xTix)O3, O. Gindele, A.Kimmel, M. G. Caina and D.M Duffy, J. Phys. Chem. C, 2015, 119 (31), 17784–17789

Computer Simulation of Defect Clusters in UO2 and their Dependence on Composition, N.A. Brincat, S.C. Parker, M. Molinari, G.C. Allen and M.T. Storr, J. Nuc. Mater, 2015, 456, 329-333

Ab initio Investigation of the Layered Uranium Oxides U3O8 and U2O5, N.A. Brincat, S.C. Parker, M. Molinari, G.C. Allen and M.T. Storr, Dalton Trans. , 2015, 44, 2613-2622

Atomistic Investigation of the Structure and Transport Properties of Tilt Grain Boundaries of UO2, N.R. Williams, M. Molinari, S.C. Parker and M.T. Storr, J. Nuc. Mater , 2015, 458, 45-55

Hydride Ion Formation in Stoichiometric UO2, J.M. Flitcroft, M. Molinari, N.A. Brincat, M. T. Storr, and S.C. Parker, Chem. Commun., 2015, 51, 16209-16212

Density Functional Theory Calculations of Defective UO2 at U3O7 stoichiometry, N.A. Brincat, M. Molinari, G.C. Allen, M.T. Storr, and S.C. Parker, J. Nuc. Mater , 2015, 467, 724-729

Theoretical models of hydrogen-induced defects in amorphous silicon dioxide, Al-M. El-Sayed, Y. Wimmer, W. Goes, T. Grasser, V. V. Afanas' ev, A.L. Shluger, Phys. Rev. B, 2015, 92(1), 014107-11

Toggling the local electric field with an embedded adatom switch, W. Steurer, B. Schuler, N. Pavlicek, L. Gross, I. Scivetti, M. Persson and G. Meyer, Nano Letters, 2015, 15, 5564

Charge-induced Dipole vs. Relativistically Enhanced Covalent Interactions in Ar-tagged Au-Ag Tetramers and Pentamers, A. Shayeghi, R. Schäfer, D. M. Rayner, R. L. Johnston and A. Fielicke, J. Chem. Phys., 2015, 143 (2), 24310

Modelling of oxygen vacancy aggregates in monoclinic HfO2: can they contribute to conductive filament formation?, S. R. Bradley, G. Bersuker, A. L. Shluger, J. Phys.: Condens. Matter, 2015, 27(41), 415401

A density functional study of oxygen vacancy formation on α-Fe2O3(0001) surface and the effect of supported Au nanoparticles, S. W. Hoh, L. Thomas, G. Jones and D. J. Willock, Research on Chemical Intermediates, 2015, 41 (12), 9587-9601

Strengthening of UK’s international position: Consortium members have a very extensive range of international collaborations with Universities and both government and industrial research laboratories worldwide. Examples of active collaborations include:

Development of embedded cluster (QM/MM) software for application in materials science (UCL, Daresbury, PNNL(USA)) – UK leader, Alexei Sokol

Modelling of phosphate nucleation (Sheffield, Potsdam, Eindhoven, Curtin (Aus)) – UK leader, John

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Harding

Modelling of perovskite solar cells (Bath, AMOLF (Netherlands), Milan, Yonsei University (S.Korea)) – UK leader, Aron Walsh

Modelling of metal centres in zeolite catalysts (UCL,Tezpur(India)) – UK leader, Richard Catlow

Modelling of the reliability and degradation of next generation nano-electronic devices (FP7-NMP-2010-Small-4; collaborative project with UCL and several European university partners) – UK leader, Alex Shluger

Electronic couplings for molecular charge transfer (UCL, Karlsruhe) – UK leader, Jochen Blumenberger

Modelling of heterogeneous catalysis (Cardiff, CSIR, Pretoria) – UK leader, Dave Willock

Modelling of metal nano-particles (Birmingham, Univ of Barcelona, TU Berlin) – UK leader, Roy Johnston

Modelling of iron sulphide catalysts for CO2 activation (Cardiff, Utrecht) – UK leader, Nora deLeeuw

Modelling of C-BN for the photocatalytic production of hydrogen (Reading, Purdue, JNCASR(Bangalore,India)) – UK leader, Ricardo Grau-Crespo

Publications including international collaborators include:

Flavin binding to the deca-heme cytochrome MtrC: Insights from computational molecular simulation, M. Breuer, K. M. Rosso, and J. Blumberger, Biophys. J., 2015, 109 (12), 2614-2624

Importance of anisotropic Coulomb interaction in LaMnO3, T.A. Mellan, F. Cora, R. Grau-Crespo, S. Ismail-Beigi, Phys. Rev. B, 2015, 92 (08), 085151 1-16

Engineering the electronic bandgaps and band edge positions in carbon-substituted 2D boron nitride: a first-principles investigation, S. N. Shirodkar, U. V. Waghmare, T. S. Fisher, R. Grau-Crespo, Phys. Chem. Chem. Phys. , 2015, 17, 13547-13552.

The interplay of metal-atom ordering, Fermi level tuning and thermoelectric properties in cobalt shandites Co3M2S2 (M = Sn, In), J. Corps, P. Vaqueiro, A. Aziz, R. Grau-Crespo, W. Kockelmann, J.C. Jumas, A.V. Powell, Chem. Mater., 2015, 27, 3946–3956

Electronic structure of porphyrin-based metal-organic frameworks and their suitability for solar fuel production photocatalysis, S. Hamad, N. C. Hernandez, A. Aziz, A. R. Ruiz-Salvador, S. Calero and R. Grau-Crespo, J. Mater. Chem. A, 2015, 3, 23458-23465

Self-regulation mechanism for charged point defects in hybrid halide perovskites, A. Walsh, D. O. Scanlon, S. Chen, X. G. Gong, and S. -H. Wei, Angew. Chem. Intl. Ed., 2015, 54, 1791-1794

Antiferromagnetism at T > 500K in the layered hexagonal ruthenate SrRu2O6, C. I. Hiley, D. O. Scanlon, A. A. Sokol, S. M. Woodley, A. M. Ganose, S. Angio, J. M. De Teresa, P. Manuel, D. D. Khalyavin, M. Walker, M. R. Lees, and R. I. Walton, Phys. Rev. B, 2015, 92, 104413

Dynamical simulations of an electronically induced solid-solid phase transformation in tungsten, S. T. Murphy, S. L. Daraszewicz, Y. Giret, M. Watkins, A. L. Shluger, K. Tanimura and D. M. Duffy, Phys. Rev. B, 2015, 92, 134110

Interaction picture density matrix quantum Monte Carlo, Fionn D. Malone, N.S. Blunt, James J. Shepherd, D.K.K. Lee, J.S. Spencer, and W.M.C. Foulkes, J. Chem. Phys., 2015, 143, 44116

Open-source development experiences in scientific software: the HANDE quantum Monte Carlo project., J.S. Spencer, N.S. Blunt, W.A. Vigor, Fionn D. Malone, W.M.C. Foulkes, James J. Shepherd, and A.J.W. Thom, J. Open Res. Software, 2015, 3, e9

Mapping Structural Changes in Electrode Materials: Application of the Hybrid Eigenvector-Following Density Functional Theory (DFT) Method to Layered Li0.5MnO2, I.D. Seymour, S. Chakraborty, D. S. Middlemiss, D. J. Wales and C. P. Grey , Chem. Mater., 2015, 12 (16), 5550-5561

Adsorption of poly acrylic acid onto the surface of calcite: an experimental and simulation study, D.J. Sparks, M.E. Romero-Gonzalez, E. El-Taboni, C.L. Freeman, S.A. Hall, G. Kakonyi, L. Swanson, S.A. Banwart and J.H. Harding , Physical Chemistry Chemical Physics , 2015, 17 (41) , 27357-27365

Tunable Porosity through Cooperative Diffusion in a Multicomponent Porous Molecular Crystal, R. Manurung, D. Holden, M. Miklitz, L. Chen, T. Hasell, S. Y. Chong, M. Haranczyk, A. I. Cooper, K. E. Jelfs, J. Phys. Chem. C, 2015, 119, 22577-22586

Solvation and Hydration of the Ceramide Headgroup in a Non-Polar Solution, R. J. Gillams, J. V.

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Busto, S. Busch, F. M. Goñi, C. D. Lorenz and S. E. McLain, J. Phys. Chem. B, 2015, 119 (1), 128-139

Atomic scale structure and properties of highly stable antiphase boundary defects in Fe3O4, K. P. McKenna, F. Hofer, D. Gilks, V. K. Lazarov, C. Chen, Z. Wang and Y. Ikuhara, Nature Communications, 2014, 5, 5740

Surface Specific Visible Light Luminescence from Composite Metal Oxide Nanocrystals, A. Sternig, J. Bernardi, K.P. McKenna and O. Diwald, J. Mater. Sci., 2015, 50, 8153

Atomic study of Fe3O3/SrTiO3 interface, D. Gilks, D.M. Kepaptsoglou, K. McKenna, L. Lari, Q.M. Ramasse, K. Matsuzaki, T. Susaki and V.K. Lazarov, Microsc. Microanal., 2015, 21, 1299

Enhancement of low-energy electron emission in 2D radioactive films, A. Pronschinske, P. Pedevilla, C. J. Murphy, E. A. Lweis, F. R. Lucci, G. Brown, G. Pappas, A. Michaelides and E. C. H. Sykes, Nature Materials, 2015, 14, 904

Computation of diffuse scattering arising from one-phonon excitations in a neutron time-of-flight single-crystal Laue diffraction experiment, M. J Gutmann, G. Graziano, S Mukhopadhyay, K. Refson, M. von Zimmerman, J. App. Cryst. , 2015, 48, 1122

Modelling the effects of surfactant loading level on the sorption of organic contaminants on organoclays, Q. Zhou, R. Zhu, S.C. Parker, J. Zhu, H. He and M. Molinari, RSC Adv., 2015, 5 (58), 47022-47030

Measuring the mechanical properties of molecular conformers, S.P. Jarvis, S. Taylor, J.D. Baran, N.R. Champness, J.A. Larsson and P. Moriarty, Nature Commun. , 2015, 5, 8338

A giant reconstruction of α-quartz (0001) interpreted as three domains of nano dauphine twins, S.D. Eder, K. Fladischer, S.R. Yeandel, A. Lelarge, S.C. Parker, E. Søndergård, and B. Holst, Scientific Reports, 2015, 5, 14545

Measuring the mechanical properties of molecular conformers., S. P. Jarvis, S. Taylor, J. D. Baran, N. R. Champness, J. A. Larsson, P. Moriarty, Nature Communications, 2015, 6, 1

Adatoms Underneath Single Porphyrin Molecules on Au(111), J. Mielke, F. Hanke, M. V. Peters, S. Hecht, M. Persson and L. Grill, J. Am. Chem. Soc., 2015, 137, 1844

Adatoms Underneath Single Porphyrin Molecules on Au(111), J. Mielke, F. Hanke, M. V. Peters, S. Hecht, M. Persson and Leonhard Grill,, J. Am. Chem. Soc., 2015, 137, 1844

Toggling the local electric field with an embedded adatom switch, W. Steurer, B. Schuler, N. Pavlicek, L. Gross, I. Scivetti, M. Persson and G. Meyer, Nano Letters, 2015, 15, 5564

Pool-BCGA: A Parallel Generation-Free Genetic Algorithm for the Ab Initio Global Optimisation of Nanoalloy Clusters, A. Shayeghi, D. Goetz, J.B.A. Davis, R. Schaefer and R.L. Johnston, Phys. Chem. Chem. Phys., 2015, 17 (3), 2104-2112

O2 Dissociation on M@Pt Core-Shell Particles for 3d, 4d and 5d Transition Metals, P.C. Jennings, H.A. Aleksandrov, K.M. Neyman, and R.L. Johnston, J. Phys. Chem. C, 2015, 119 (20), 11031-11041

Optical Absorption Spectra and Structures of Ag6+ and Ag8+, A. Shayeghi, D.A. Goetz, R.L. Johnston and R. Schaefer, Eur. Phys. J. D, 2015, 69 (6), 152

Charge-induced Dipole vs. Relativistically Enhanced Covalent Interactions in Ar-tagged Au-Ag Tetramers and Pentamers, A. Shayeghi, R. Schäfer, D. M. Rayner, R. L. Johnston and A. Fielicke, J. Chem. Phys., 2015, 143 (2), 24310

The Birmingham Parallel Genetic Algorithm and its Application to the Direct DFT Global Optimisation of IrN (N = 10-20) Clusters, J. B. A. Davis, A. Shayeghi, S. L. Horswell and R. L. Johnston, Nanoscale, 2015, 7 (33), 14032-14038

Messenger or Modifier? The Nature of Argon Bonds to Mixed Gold-Silver Trimers, A. Shayeghi, R. L. Johnston. D. M. Rayner, R. Schäfer and A. Fielicke, Angew. Chem. Int. Ed., 2015, 54 (36), 10675-10680

Are the Crystal Structures of Enantiopure and Racemic Mandelic Acids Determined by Kinetics or Thermodynamics?, R. K. Hylton, G. J. Tizzard, T. L. Threlfall, A. L. Ellis, S. J. Coles, C. C. Seaton, E. Schulze, H. Lorenz, A. Seidel-Morgenstern, M. Stein, and S. L. Price, J. Am. Chem. Soc., 2015, 137 (34), 11095-11104

Concomitant conformational dimorphism in 1,2-bis(9-anthryl)acetylene, R. I. Goldstein, R. Guo, C. Hughes, D. P. Maurer, T. R. Newhouse, T. J. Sisto, R. R. Conry, S. L. Price and D. M. Thamattoor , CrystEngComm, 2015, 17 (26), 4877-4882

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Photoinduced Br Desorption from CsBr Thin Films Grown on Cu (100), M.T. E. Halliday, A. G. Joly, W. P. Hess, A. L. Shluger, J. Phys. Chem. C, 2015, 119(42), 24036-24045

Modelling of oxygen vacancy aggregates in monoclinic HfO2: can they contribute to conductive filament formation?, S. R. Bradley, G. Bersuker, A. L. Shluger, J. Phys.: Condens. Matter, 2015, 27(41), 415401

Optical signatures of intrinsic electron localization in amorphous SiO2, A.-M. El-Sayed, K. Tanimura, A. L. Shluger, J. Phys.: Condens. Matter., 2015, 27(26), 265501-6

Hole trapping at hydrogenic defects in amorphous silicon dioxide, Al-M. El-Sayed, M. B. Watkins, T. Grasser, V. V. Afanas’ev, A. L. Shluger, Microel. Eng., 2015, 147, 141-144

Role of entropic effects in controlling the polymorphism in formate ABX3 metal–organic frameworks, G. Kieslich, S. Kumagai, K. T. Butler, T. Okamura, C. H. Hendon, S. Sun, M. Yamashita, A. Walsh, A. K. Cheetham, Chem. Comm., 2015, 51, 15538-15541

Influence of the exchange-correlation functional on the quasi-harmonic lattice dynamics of II-VI semiconductors, J. M. Skelton, D. Tiana, S. C. Parker, A. Togo, I. Tanaka and A. Walsh, J. Chem. Phys., 2015, 143, 64710

Crystalline adducts of the Lawsone molecule (2-hydroxy-1,4-naphthaquinone): optical properties and computational modelling, A. R. Pallipurath, J. M. Skelton, A. Delori, C. Duffy, A. Erxleben and W. Jones, CrystEngComm, 2015, 17, 7684

Solid-state chemistry of glassy antimony oxides, C. E. Kim, J. Skelton, A. Walsh and A. Soon, J. Mater. Chem. C, 2015, 3, 11349

A density functional study of oxygen vacancy formation on α-Fe2O3(0001) surface and the effect of supported Au nanoparticles, S. W. Hoh, L. Thomas, G. Jones and D. J. Willock, Research on Chemical Intermediates, 2015, 41 (12), 9587-9601

Future Vision: The consortium will stay at the cutting edge of materials modelling with acceleration in the current trend to increasingly predictive modelling of real systems of growing complexity. We envisage that new capabilities will be achieved in all our themes leading to the following types of problem being addressed:

In Catalysis, we will develop the capability of modelling accurately and predictively the rates of catalytic reactions of industrial importance allowing the prediction of the effects on real catalytic processes of variation in chemical and physical parameters.

In Energy Storage, we will enhance the methodology of modelling accurately the energy densities and ion diffusion rates in lithium and sodium battery materials of technological importance for next-generation portable electronics and electric vehicles.

In Nano and Defect Structures, we will develop novel approaches to improve the accuracy in predicting defect structures and spectroscopic properties in novel nano-materials and will unravel complex defect dynamics and reactions in polycrystalline and amorphous materials in conditions relevant for new technologies.

In Environment, the major challenges will concern understanding radiation damage processes to

develop new materials for high level nuclear waste disposal; and the development both of new

methods for carbon capture and absorptive materials for environmental remediation

In Energy Generation, advanced modelling at all length and time scales is being used to optimise

and discover new materials for the next generation solar, thermal, nuclear, biomass, wind and

efficient low carbon fossil fuel technologies.

In Surfaces and interfaces, we will support research on fundamental and applied research on

reactions and processes at the exterior of particles, influencing processes as diverse as ice

crystallisation to separation of petroleum fractions within porous materials.

In Organic and Soft matter, we aim to develop our ability to predict the self-assembly, structure and

emergent properties of both small molecule and macromolecular organic materials, informing in-

depth understanding and design of organic and soft matter systems with targeted properties.

In Biomaterials, a wide range of biologically relevant materials is studied, and we will continue to build on our shared expertise to expand this range to new materials and systems.