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This document summarises the views expressed by the Italian Computing and Data Initiative (ICDI) in response to the open consultation for the EOSC Strategic Research and Innovation Agenda (SRIA), closed on the 31st of August. It provides insightful input and suggestions about the current draft of the SRIA document shared with the wider EOSC community, with the aim of helping to shape the future vision of the European Open Science Cloud.

In this work molecular simulations are used to probe the gas adsorption properties of amorphous chalcogenide nanopores. A realistic atom-scale model, derived by first-principles calculations, of glassy chalcogenide surface is considered for the present study. Nitrogen adsorption and condensation at 77 K in pores of different widths are simulated for characterization purposes. The adsorption of carbon dioxide, methane, hydrogen, and their mixtures is investigated at 298 K. Analysis of the adsorption data shows nice agreement with the prediction of obtained using the Ideal Adsorbed Solution Theory. A detailed comparison with experimental literature data is also proposed and discussed. We also address the effect of the surface chemistry on the gas adsorption by studying both bare and hydrogenated chalcogenide surfaces. We show here that porous glassy chalcogenide exhibits highly selective gas adsorption properties and can strongly discriminate among gases on the basis of their interaction with the chalcogenide surface.

28th European Photovoltaic Solar Energy Conference and Exhibition; 3949-3952, This paper reports on progress towards the development of an infrastructure to integrate existing modelling tools, and thus allow modelling of the entire solar cell value chain, from initial material parameters to the long-term energy yield of complete PV systems. Currently, the infrastructure has been developed and successfully tested from the material to the system level, for three different cell technologies using 13 different programs across 7 European institutes. Input data can be either modelled or experimentally measured. Further work will focus on: comparison of the simulation results with experimentally measured system data; defining standard interface protocols to simplify the information transfer; and predicting the yearly energy output for installed PV systems.

We have characterized by total-energy calculations and molecular-dynamics simulations the two crystalline phases ~ C54 and C49 ! of TiSi 2 in a wide range of temperatures. We have also produced and analyzed the amorphous and the liquid phases. Structural and thermoelastic properties are calculated and reported for all the phases. The molecular-dynamics simulations are based on an original set of parameters for the interatomic potential in the framework of the tight-binding approach. The intrinsic difference between the C54 and C49 phases is addressed and discussed by looking at the structural and the electronic properties

The thermodynamic behavior of the carbon schwarzite fcc (Formula presented) has been studied by tight-binding molecular-dynamics simulations at constant temperature and pressure. The system is totally (Formula presented) bonded and it can be represented as a folded graphite sheet made by hexagonal and heptagonal rings. The structure has a density (Formula presented) as low as (Formula presented) at (Formula presented) K and a bulk modulus B, evaluated by measuring the volume variation upon application of an external hydrostatic load, as large as (Formula presented) Mbar. At (Formula presented) K, the structure unfolds via a topological transformation, which brings the value of the topological connectivity of the structure (Formula presented) from (Formula presented) (for a cell including four molecules) to (Formula presented) (which is the value of a graphite sheet). The behavior of the structural, dynamical, and electronic-structure properties has been evaluated in the whole temperature range, below and above the temperature of the topological transition.

In this paper we describe the parallelization of a molecu­lar dynamics code, based on a Tight-Binding Hamiltonian, on a DMMP parallel platform. The data-parallel implementation has been carried out within the HPF framework, and tested on IBM SP2 architectures. The integration of an optimized parallel library routine (PESSL) for the full diagonalization of large symmetric matrices is also described. The scalability of this approach, the performance of the parallel code and that of the PESSL routine are shown. © Springer-Verlag Berlin Heidelberg 1998.

A genetic algorithm for ground-state structure optimization of a Palladium atomic cluster has been developed and ported on a SIMDMIMD parallel platform. The SIMD part of the parallel platform is represented by a Quadrics/APE100 consisting of 512 floating point units while the MIMD part is formed by a cluster of workstations. The proposed algorithm contains a part where the genetic operators are applied to the elements of the population and a part which performs a further local relaxation and the fitness calculation via Molecular Dynamics. These parts have been implemented on the MIMD part and on the SIMD one, respectively. Results have been compared to those generated by using a Simulated Annealing technique. © Springer-Verlag Berlin Heidelberg 1996.

A Molecular Dynamics code, utilized for the study of atomistic models of metallic nanostructured materials, has been ported on MIMD platforms by means of the PVM message passing libraries. The nanostructured materials represent a challenging problem for the parallelization strategies due to their intrinsic dishomogeneity and to the slow relaxation toward the equilibrium configuration. The interaction potential, derived from the second moment approximation of a tight-binding Hamiltonian, the Parrinello-Rahman-Nosé and the VI order predictor-corrector Gear algorithms are implemented efficiently in the parallel code. The parallelization strategies utilized and the molecular dynamics code are described in detail. Benchmarks on several MIMD platforms allow performances evaluation and future improvements. © Springer-Verlag Berlin Heidelberg 1996.

The thermodynamic stability of hydroxylated graphane, that is, fully sp3 graphene derivatives coordinated with -H and -OH groups, has been recently demonstrated by ab initio calculations. Within the density functional theory approach, we investigate the electronic property modifications of graphane by progressive hydroxylation, that is, by progressively substituting -H with -OH groups. When 50% of graphane is hydroxylated, the energy bandgap reaches its largest value of 6.68 eV. The electronic affinity of 0.8 eV for graphane can widely change in the 0.28-1.60 eV range depending on the geometric configuration. Hydroxylated graphane has two interfaces with vacuum, hence its electron affinity can be different on each interface with the formation of an intrinsic dipole perpendicular to the monolayer. We envisage the possibility of using hydroxylated graphane allotropes with tunable electronic affinity to serve as interfacial layers in 2D material-based heterojunctions.

Laser-driven proton acceleration, as produced during the interaction of a high-intensity (I > 1 × 1018 W/cm2), short pulse (

Development of characterization methods and tools to address structural, electronic and optical properties of materials from the atomic-scale models. Characterization procedures to assess the reliability of the numerical models. Application of MDFT code to supercapacitor materials screening. Coupling of codes to increase accurateness of the computed properties. Modeling of materials at different lenght scales. Description of applications via continuous models. Model settings to design large scale simulations to address accurately macroscopic properties., H2020

The solubilization mechanism of lipid membranes in the presence of Triton X-100 (TX-100) is investigated at molecular resolution using molecular dynamics (MD) simulations. Thanks to the large time and length scales accessible by the hybrid particle-field formulation of the models employed here, the complex process of membrane solubilization has been studied, with the goal of verifying the three stage model reported in the literature. DPPC lipid bilayers and vesicles have been studied at different concentrations of the TX-100 detergent employing coarse grained (CG) models. Systems up to ∼600.000 beads, corresponding to more than 2 millions heavy atoms, have been simulated. Moreover, in order to clarify several experimental pieces of evidence, both slow and fast detergent partition scenarios have been investigated. Flat and curved (vesicles) lipid bilayer surfaces, interacting with TX-100, have been considered to study the curvature effects on the detergent partition rate in the membrane. Shape and conformational changes of mixed DPPC/TX-100 vesicles, as a function of TX-100 content, have also been studied. In particular, high curvature surfaces, corresponding to a higher local TX-100 content, promote a membrane rupture. In flat lipid surfaces, on the time scale simulated the detergent partition is almost absent, following a different pathway of the solubilization membrane mechanism. © 2017 the Owner Societies.

Optimization of all numerical codes ported in the infrastructure and used for supercapacitors, PV and batteries. The scope of deliverable D3.2 is to report the new advances in the field of materials for energy that comes from the search of new methodologies and models that could be more efficient on the new generation of computer hardware for exascale. In this respect, deliverable D3.2 is a transversal deliverable that report the new advances related to activities described in task T3.2, T3.3 and T3.4., H2020

Doping of MgH2 with transition metals and their oxides is well-known procedure to improve its hydrogen (de) sorption properties, namely to lower the temperature of desorption and to achieve the kinetics speedup. In order to assess the influence Ti and TiO2 doping has on H mobility and to characterize structurally and electronically observed differences, MgH2-Mg interface doped with both Ti and TiO2 have been studied using ab-initio interface molecular dynamics and bulk calculations. Results suggest different mechanisms of MgH2 structure destabilization. The presence of dopants significantly stabilize MgH2-Mg interface, which is confirmed by work of adhesion computation. Calculated formation energies show that interface system with doped TiO2 is more stable. In terms of H mobility, molecular dynamics simulations confirm that Ti doping is more effective than TiO2 in lowering the desorption temperature. The mobility of hydrogen atoms close to dopant is much higher in the case of Ti than in the case of TiO2. Electronic structure characterization reveals that oxygen atoms with high electron affinity forms more pronounced ionic bonding with Ti and the other neighbor Mg atoms. This in turn cause a shorter Ti-H bonds in first coordination than in the case of Ti doping and further reduction of H atoms mobility. This is in accordance with molecular dynamics predictions. (C) 2016 Elsevier B.V. All rights reserved.

The corrosion of structural materials used in fast nuclear reactor design is a current major problem. It is due to the use of liquid metal as a coolant candidate in the heat transfer system. The liquid metal as lead-bismuth eutectic was found to make high corrosion to structural material as steel. One of the solutions of this problem is to inject some inhibitor into liquid metal. In this current work we simulate the effect of nitrogen injection as inhibitor candidate. The simulation will predict the proper concentration of injected nitrogen and also observe the microscopic structure of the material before and after injection to know the ability of nitrogen as an inhibitor. The simulation follows the molecular dynamics method and for preliminary study we use iron material rather than steel. We also use lennard-jones potential for simplification of the study. It is from our simulation we see nitrogen shows better corrosion mitigation compare with oxygen as in our previous study. The effective inhibition can be achieved by injecting at least 0.056wt.% nitrogen. This amount seems to be able to reduce the corrosion level of iron till about 99.5% for high corrosion at temperature 750 °C. © Published under licence by IOP Publishing Ltd.

A multiscale scheme is proposed and validated for Triton X-100 (TX-100), which is a detergent widely employed in biology. The hybrid particle field formulation of the model allows simulations of large-scale systems. The coarse-grained (CG) model, accurately validated in a wide range of concentrations, shows a critical micelle concentration, shape transition in isotropic micellar phase, and appearance of hexagonal ordered phase in the experimental ranges reported in the literature. The fine resolution of the proposed CG model allows one to obtain, by a suitable reverse mapping procedure, atomistic models of micellar assemblies and of the hexagonal phase. In particular, atomistic models of the micelles give structures in good agreement with experimental pair distance distribution functions and hydrodynamic measurements. The picture emerging by detailed analysis of simulated systems is quite complex. Polydisperse mixtures of spherical-, oblate-, and prolate-shaped aggregates have been found. The shape and the micelle behavior are mainly dictated by the aggregation number (Nagg). Micelles with low Nagg values (∼40) are spherical, while those with high Nagg values (∼140 or larger) are characterized by prolate ellipsoidal shapes. For intermediate Nagg values (∼70), fluxional micelles alternating between oblate and prolate shapes are found. The proposed model opens the way to investigations of several mechanisms involving TX-100 assembly in protein and membrane biophysics. © 2015 American Chemical Society.