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The EMMC Roadmap defines a path forward for materials modelling and digitalisation of materials sciences. It is the culmination of five years of knowledge‐ and experience‐gathering, by the EMMC, on the needs of European materials industry in the modelling field. The EMMC Roadmap acknowledges the significant progress that has been made over the past years, but equally identifies gaps, and provides direction for achieving the ultimate vision of: Having an agile European materials industry with intelligent enterprises that maximise and integrate the utility of digital materials sciences knowledge &nbsp

Algorithms and methods to couple and link multiple model types are often needed to tackle some of the most challenging problems in materials' simulations. Developing these represents both a complex and fascinating intellectual challenge, and a pressing need to tackle realistic systems in applied and industrial research. We summarize here the conclusions of the meeting, where we have identified the areas where coupling- and linking efforts would have the greatest impact, and which should be the policy recommendations to make to the Commission to facilitate this impact. This expert meeting, convened by the European Materials Modelling Council and hosted by CECAM, gathered some of the foremost experts across different domain areas, with the goal of identifying a roadmap for coupling and linking simulations that can act as a manifesto for the field, and inform future policy makers of the algorithmic and methodological developments needed and of their relevance and role in accelerating simulation-driven innovation., Please download and cite Version 2 as this comprises the complete list of co-authors.

Algorithms and methods to couple and link multiple model types are often needed to tackle some of the most challenging problems in materials' simulations. Developing these represents both a complex and fascinating intellectual challenge, and a pressing need to tackle realistic systems in applied and industrial research. We summarize here the conclusions of the meeting, where we have identified the areas where coupling- and linking efforts would have the greatest impact, and which should be the policy recommendations to make to the Commission to facilitate this impact. This expert meeting, convened by the European Materials Modelling Council and hosted by CECAM, gathered some of the foremost experts across different domain areas, with the goal of identifying a roadmap for coupling and linking simulations that can act as a manifesto for the field, and inform future policy makers of the algorithmic and methodological developments needed and of their relevance and role in accelerating simulation-driven innovation.

Algorithms and methods to couple and link multiple model types are often needed to tackle some of the most challenging problems in materials' simulations. Developing these represents both a complex and fascinating intellectual challenge, and a pressing need to tackle realistic systems in applied and industrial research. We summarize here the conclusions of the meeting, where we have identified the areas where coupling- and linking efforts would have the greatest impact, and which should be the policy recommendations to make to the Commission to facilitate this impact. This expert meeting, convened by the European Materials Modelling Council and hosted by CECAM, gathered some of the foremost experts across different domain areas, with the goal of identifying a roadmap for coupling and linking simulations that can act as a manifesto for the field, and inform future policy makers of the algorithmic and methodological developments needed and of their relevance and role in accelerating simulation-driven innovation.

First principles modelling, using e.g. the density functional theory (DFT), has become a valuable tool in materials research. However, today’s computer resources limit the size and time scales that can be studied with such techniques, thereby hindering the full utilization of computational chemistry for large-scale systems in practice. Thus, new developments of reliable approximate and/or parameterized methods are needed. One promising approximate method, conceptually similar to the DFT, is the self-consistent charge density functional based tight binding method (SCC-DFTB). SCC-DFTB calculations are parameterized against DFT data (see illustration in Figure 1) and are at least two orders of magnitude faster than a standard semi-local DFT calculation. However, to obtain an accuracy comparable to DFT for complex oxides is a task that has proven to be a challenge. In this talk, I will present our SCC-DFTB parameterization effort for the technologically important reducible oxide CeO2.1 I will discuss the strategy we have developed for the parameterization and the special complication that follows with reducible oxides. Furthermore, I will demonstrate the applicability of the generated parameters and show results from validation by comparing to data obtained from DFT calculations for CeO2. I will show results for oxygen vacancy formation in various ceria structures of different dimensionality, ranging from 0D (nano) to 3D (bulk) and for oxygen adsorption on ceria nanoparticles and preliminary results regarding ceria nanoparticle agglomeration.

Polarons in metal oxides are important in processes such as catalysis, high temperature superconductivity, and dielectric breakdown in nanoscale electronics. Here, we study the behavior of electron small polarons associated with oxygen vacancies at rutile TiO2(110), using a combination of low temperature scanning tunneling microscopy (STM), density functional theory, and classical molecular dynamics calculations. We find that the electrons are symmetrically distributed around isolated vacancies at 78 K, but as the temperature is reduced, their distributions become increasingly asymmetric, confirming their polaronic nature. By manipulating isolated vacancies with the STM tip, we show that particular configurations of polarons are preferred for given locations of the vacancies, which we ascribe to small residual electric fields in the surface. We also form a series of vacancy complexes and manipulate the Ti ions surrounding them, both of which change the associated electronic distributions. Thus, we demonstrate that the configurations of polarons can be engineered, paving the way for the construction of conductive pathways relevant to resistive switching devices.

In a recent article, Gr\"{u}nebohm et al. [Phys. Rev. B 84 132105 (2011), arXiv:1106.2820] report that they fail to reproduce the A2u ferroelectric instability of TiO2 in the rutile structure calculated with density functional theory within the PBE-GGA approximation by Montanari et al. [Chem. Phys. Lett 364, 528 (2002)]. We demonstrate that this disagreement arises from an erroneous treatment of Ti 3s and 3p semi-core electrons as core in their calculations. Fortuitously the effect of the frozen semi-core pseudopotential cancels the phonon instability of the PBE exchange-correlation, and the combination yields phonon frequencies similar to the LDA harmonic values. Gr\"{u}nebohm et al. also attempted and failed to reproduce the soft acoustic phonon mode instability under (110) strain reported by Mitev et al. [Phys. Rev. B 81 134303 (2010)]. For this mode the combination of PBE-GGA and frozen semi-core yields a small imaginary frequency of 9.8i. The failure of Gr\"{u}nebohm et al. to find this mode probably arose from numerical limitations of the geometry optimization approach in the presence of a shallow double well potential; the optimization method is not suitable for locating such instabilities., Comment: 5 pages

Graphical abstract Highlights ► Solvation of a linear anionic gold complex by a very polar solvent. ► Development of a force field tailored to the particular system. ► Molecular dynamics simulation for atom-level analysis. ► X-ray diffraction and cluster data for consistency and interpretation., The solvation structure around the dicyanoaurate(I) anion (Au(CN)2−) in a dilute nitromethane (CH3NO2) solution is presented from X-ray diffraction measurements and molecular dynamics simulation (NVT ensemble, 460 nitromethane molecules at room temperature). The simulations are based on a new solute–solvent force-field fitted to a training set of quantum-chemically derived interaction energies. Radial distribution functions from experiment and simulation are in good agreement. The solvation structure has been further elucidated from MD data. Several shells can be identified. We obtain a solvation number of 13–17 nitromethane molecules with a strong preference to be oriented with their methyl groups towards the solute.

We present a theoretically oriented analysis of the appearance and properties of plausible candidates for the anionic defects observed in scanning tunneling microscopy (STM) experiments on CeO2(111). The simulations are based on density functional theory (DFT) and cover oxygen vacancies, fluorine impurities and hydroxyl groups in the surface and sub-surface layers. In the surface layer, all three appear as missing spots in the oxygen sublattice in filled state simulated STM images, but they are distinguishable in empty state images, where surface oxygen vacancies and hydroxyls appear as, respectively, diffuse and sharp bright features at oxygen sites, while fluorine defects appear as triangles of darkened Ce ions. In the sub-surface layer, all three defects present more complex patterns, with different combinations of brightened oxygen ion triangles and/or darkened Ce ion triangles, so we provide image maps to support experimental identification. We also discuss other properties that could be used to distinguish the defects, namely their diffusion rates and distributions.

In this work, dispersion-corrected density functional theory (DFT-D3), has been used to investigate interactions between important intermediates in lignin depolymerization and a palladium catalyst. The keto structure 2-phenoxy-1-phenylethanone and its enol tautomer have been used to model reactive intermediates derived from lignin. To investigate how the adsorption energies are affected by adsorbate coverage, we have used two different Pd(111) super cells; one smaller p(6 × 4) and one larger p(6 × 6). In the gas phase, the staggered conformer of the keto tautomer is more stable than both the eclipsed form of the keto tautomer and as expected much more stable than the E-enol tautomer. However, in interaction with the palladium surface, the E-enol tautomer has a similar binding energy as the keto tautomer. Also, the eclipsed conformer of the keto tautomer is more stable than the staggered conformer of the keto tautomer when adsorbed to the palladium. We found that the coverage, that is concentration of molecules on the surface had a pronounced effect on the adsorption energies. At higher coverage, both the keto and enol models prefer to adsorb on an atop configuration to the surface. Furthermore, we found that both the keto and the enol tautomers bind strongly to the surface through their phenyl rings. Despite the strong binding of the phenyl groups, the enol adsorbs to the surface through a chemisorption by cleavage of the C═C bond, that leads to two types of di-sigma complexes depending on the position of the newly formed Pd–C sigma bonds. The generated complex is a key intermediate in the subsequent depolymerization through cleavage of a C–O bond. Our simulations show that there is an intermolecular repulsion between adsorbates on the surface, and consequently, the molecules were found to bind more strongly to the surface at low coverages (by 8-14 kcal/mol). These results are important for experimental design purposes; as previous experiments have shown that the enol form is key for an efficient β-O-4′ bond cleavage and implies that low concentration reactions are favored.

Methods and tools are constantly sought by manufacturing organisations to help reduce the time to reach decisions and solve problems, to reduce the costs of running the business, and to improve solution flexibility by providing different perspectives to a given question or problem. Materials modelling is seen as part of an emerging toolkit to help reach these business goals, however, realising the benefits of materials modelling in development areas such as the ‘sweet spots’ requires investment in a framework to help materials modelling plug-in to the business. In this work, we describe the components of Business Decisions Support Systems for materials modelling.&nbsp