Material Science
Abinitiosimulation of twodimensional networks on the surface of water
Molecules adsorbed on surfaces play an important role in catalysis, surface science, and nanotechnology. Traditionally, research has focused on various adsorbates atop metals and metal oxides using computational and surfacescience techniques. More recently, however, it was demonstrated that ordered monolayer networks can also be formed on the surface of liquid water by using metal ions to bind together multidentate precursor molecules [1, 2]. As these twodimensional polymers are challenging to analyze, computational methods can provide valuable insight into their formation and structure.
In this contribution we present largescale ab initio molecular dynamics (MD) simulations of the formation of a network of tristerpyridinederived molecules (TTPB) on a water surface. We use the Piz Daint supercomputer at CSCS and the cp2k code to study the dynamics of the molecule on the surface, the mechanism of Zn ion insertion from the solution and the subsequent linking of molecules into aggregates. We employ advanced MD methods to quantify the free energy surface of the involved processes. Our results provide detailed insight into onsurface and subsurface diffusion in this system and chemical reactions of TTPB on the surface of water.
[1] A. D. Schlüter et al., Angew. Chem. Int. Ed. 2012, 50, 7879.
[2] O. Sakata et al., Cryst. Eng. Commun. 2011, 13, 5538.
Anisotropydriven enhancement of spincorrelations
We study the Hubbard model on different lattices  coupled 1D chains, coupled 2D layers made of square lattice, layered honeycomb lattice  and investigate the thermodynamic properties by the dynamical cluster approximation.
We find that the shortrange spin correlations are significantly enhanced for the anisotropic models in the direction with stronger tunneling amplitudes when compared to the isotropic 3D cubic system. Our results provide a thermometer for the quantum simulation experiment of ultracold fermions in an optical lattice and allow an quantitative estimate of the excess entropy during the lattice loading.
We furthermore investigate the dependence of the critical temperature (entropy) at the Neel transition on anisotropy and lattice geometry.
Calculation of local properties
Vibrational spectra provide extremely valuable information in the
investigation of molecules and solids. In particular, Infrared (IR) and
Raman spectroscopy are nowadays standard techniques in analytical
chemistry and routinely applied for the exploration of molecular
structures and reaction mechanisms. There exist certain rules of thumb
for the assignment of bands in the spectra but, still, the interpretation
of experimental spectra is often not straightforward.
Calculations can be of great help allowing the targeted study of specific
structures. In addition, the influence of the environment can be
investigated. Solvent effects, for instance, can be included in the
calculations via explicit solvent molecules or computationally cheaper
continuum solvation models. In order to get a more detailed
interpretation of the vibrational spectra, it is desirable to determine
the impact of certain molecules/atoms on the bands in the calculated
spectra. This can be achieved by decomposition of the measured
properties. In this way, it is possible to quantify the contributions of,
e.g., solute and solvent molecules and adsorbates on solids.
Calculations of vibrational spectra usually rely on the doubleharmonic
approximation [1], which is based on an entirely static picture. A more
sophisticated approach is the employment of ab initio molecular dynamics
that considers conformational dynamics and solvent effects at finite
temperatures. Vibrational spectra are then calculated via time
correlation functions of certain properties [2,3]. In case of IR and
Raman spectroscopy, these properties are the electric dipole and the
electricdipoleelectricdipole polarizability, respectively. Computation
of molecular contributions thus requires the evaluation of local electric
dipoles and local electricdipole‹electricdipole polarizabilities,
respectively.
We present a comparison of calculated and experimental spectra and
discuss the impact of different approximations made in the calculation
and the evaluation of local properties [4].
References:
[1] E. B. Wilson Jr., J. C. Decius, P. C. Cross, Molecular Vibrations,
McGrawHill, New York (1955).
[2] R. G. Gordon, J. Chem. Phys., 42 3658 (1955).
[3] D. A. McQuarrie, Statistical Mechanics, University Science Books,
Sausalito, CA (2000).
[4] S. Luber, J. Phys. Chem. A, 117 2760 (2013).
Multiferroic aurivillius phases: the case of Bi5FeTi3O15 by Ab Initio
The Aurivillius phases form a family of naturally layeredperovskites materials with good ferroelectric properties [1]. Bi5MnTi3O15 (BFTO) is perhaps the simplest known member of this family that also incorporates magnetic degrees of freedom. However, due to the low concentration of magnetic cations in similar systems, it is unclear how longrange multiferroic behaviour can be achieved. For example, room temperature ferromagnetism has been reported for Bi5Co0.5Fe0.5Ti3O15 [2], in contrast with no magnetic order found in Bi5CrTi3O15 [3]. To address this question, we establish the ferroelectric and magnetic properties of BFTO, using ab initio electronic structure calculations, comparing two commonly used exchangecorrelation functionals: PBE and PBEsol. We then discuss a potential site preference for Fe3+ and its impact on the polarisation and magnetic couplings. In addition, a brief comparison with Bi5MnTi3O15 will be made.
[1] C. APaz de Araujo, J. D. Cuchiaro, L. D. McMillan, M. C. Scott, and J. F. Scott, Nature, 374 (1995) 627629
[2] X. Mao, W. Wang, X. Chen, and Y. Lu, Applied Physics Letter, 95 (2009)
[3] A. T. Giddings, M. C. Stennett, D. P. Reid, E. E. McCabe, C. Greaves, and N. C. Hyatt, Journal of Solid State Chemistry, 184 (2011) 252263
The highthroughput infrastructure AiiDA and the study of local polarization in perovskites
"Materials by design" is a new and extremely powerful approach in Materials Science, where rather than choosing one material and calculating its properties, one identifies instead a desired property and looks for the best material that optimizes it. This approach requires though to build large databases of computed properties of materials.
A key challenge becomes therefore the need of a "materials' informatics" infrastructure to automatically prepare, execute and monitor workflows of calculations for large classes of materials, and then retrieve and store the results in a format that is easily browseable and queryable. To this aim, we are developing an opensource platform for high–throughput (AiiDA: "Automated Interactive Infrastructure and Database for Atomistic calculations"), that uses an advanced storing scheme to allow for highly flexible queries, combined with a REST API that exposes in a standard format the data stored in the database for further programmatic access.
After describing the infrastructure, we will show some examples of application, focusing in particular on the study of the local polarization in perovskites. Many of these systems display a hightemperature paraelectric cubic phase (with zero net polarization), whose microscopic nature is still debated. Indeed, by performing a systematic study of a selected class of these systems, we are able to identify different behaviors, and in some materials like BaTiO3 and KNbO3 we find the emergence of local ferroelectric dipoles even in the paraelectric phase.
First principles study of the electrocaloric effect in strained BaTiO3
The electrocaloric (EC) effect  a reversible change in temperature of a material by applying an external electric field  has been known for a very long time [1]. Recently however, the discovery of a "giant electrocaloric effect" [2] has stimulated extensive work on the EC effect, due to its huge potential to increase the efficiency of cooling devices. We have studied how misfit strain affects the EC temperature change in bulk BaTiO3.
We have performed molecular dynamics simulations for an effective Hamiltonian based on firstprinciples density functional theory [3]. The calculated EC temperature change Delta _T reduces when BaTiO3 is only clamped but not strained, but increases again with increasing misfit strain. Further with increasing misfit strain, there is a shift in the Delta_T peak towards higher temperatures. Therefore the misfit strain can be utilized in two ways  (i) to enhance the EC temperature change and (ii) to achieve a maximal effect in the temperature range of interest for a given application.
Further, we have compared the results from direct simulations of Delta_T with its indirect estimation using a Maxwell relation. This allows us to examine how the order of the phase transition and the rate of change of the applied field affects the EC temperature change.
[1] J. F. Scott, Annu. Rev. Mater. Sci. 41, 229 (2011).
[2] A. S. Mischenko, et al., Science 311, 1270 (2006).
[3] T. Nishimatsu, et al., Phys. Rev. B 82, 134106 (2010).
Firstprinciples Fermi surface characterization of hole doped PbTe
Doped PbTe has raised increased interest because of its peculiar properties. In particular, it shows enhanced thermoelectricity, topological insulator behaviour and a charge Kondo effect, depending on the dopant atom. Here we investigate the nature of the Fermi surface in holedoped PbTe using firstprinciples calculations. We begin by comparing recent experimental characterizations of the Fermi surface by means of effective masses, band offsets and de Haasvan Alphen frequencies with results from density functional theory (DFT). We find that the values of these properties depend strongly on the choice of exchangecorrelation functional and identify functionals that give good agreement with experiment. Our results indicate appropriate methodologies for firstprinciples studies of dopedPbTe, and give insights into the origin of the charge Kondo effect.
Firstprinciples simulation of electron transport in realistically large nanoelectronic devices
In light of technological challenges involved in manufacturing nanoscale electronic devices, the development of fast, accurate, and reliable computeraided design tools with atomistic simulation capabilities is becoming a necessity to accelerate the design of new prototypes and reduce the development cost. Density functional theory (DFT) based quantum transport approaches can rigorously model electron transport phenomena in nanometersized devices while taking into account the material properties of the simulated structure from firstprinciples. In this context, we aim at developing an efficient massively parallel simulator based on DFT and Nonequilibrium Green's Function (NEGF) methods that can simulate realistically large nanostructures with active regions composed of tens of thousands of atoms. Our approach is coupling the DFT simulation package, CP2K, and the quantum transport simulator, OMEN, and leveraging their respective strengths such accurate and efficient algorithms, high scalability, and wide range of applications.
Linear scaling Ehrenfest molecular dynamics
With the available computational power growing according to Moore's law, ever larger systems can be investigated with increasingly advanced methods and new algorithms. For electronic structure calculations on systems containing a few thousand atoms, linear scaling algorithms are essential. For ground state DFT calculations, linear scaling has already been demonstrated for millions of atoms in the condensed phase [J. VandeVondele, U. Borštnik, J. Hutter, 2012]. Here, we extend this work to electronically excited states, for example, to make UV/VIS spectroscopy or investigations of the electron injection process in dyesensitized solar cells possible. We base our approach on nonadiabatic molecular dynamics, in particular on Ehrenfest molecular dynamics (EMD). The formalism, based on the density matrix, allows for linear scaling based on the sparsity of the density matrix and naturally incorporates density embedding methods such as the KimGordon approach. First benchmark results will be presented.
Local density fitting within a Gaussian and plane waves approach
A local density fitting technique is introduced for KohnSham (KS) density functional theory calculations using a mixed Gaussian and plane waves (GPW) approach. The computationally most expensive step in construction of the KS matrix is the evaluation of the Coulomb matrix. The latter requires the calculation of twoelectron integrals with the characteristic O(N^4) problem. Baerends et al. [1] introduced a local resolution of identity approach (LRI), where the atomic pair densities are approximated by an expansion in onecenter fit functions reducing the scaling order to O(N^3).
The LRI approach is used in the Amsterdam density functional code and proved to be accurate and efficient [2].
In this work, the LRI technique was adapted for usage in a GPW framework (LRIGPW) and implemented in the CP2K program [3] package. The fitted density is employed for evaluation of Coulomb as well as exchangecorrelation potential. GPW scales already linearly with respect to system size since the plane wave expansion of the density is exploited to solve the Poisson equation in Fourier space. This leads to an O(N) process for the evaluation of the Coulomb matrix. Thus, no improvements in terms of scalability can be expected for LRIGPW. However, the prefactor for building the KS matrix is reduced resulting in a systemdependent speedup of the calculation. Furthermore, the scalability of the gridbased calculation and integration of the potential with respect to number of CPUs can be simplified and improved.
References:
[1] E.J. Baerends, D.E. Ellis, P. Ros, Chem. Phys., 1973, 2, 41.
[2] G. te Velde et al., J. Comput. Chem., 2001, 22, 931.
[3] The CP2K developers group, CP2K is freely available from: http://www.cp2k.org
Magnetic properties of multiferroic TbMnO_3
We use abinitio calculations to investigate the magnetic properties of multiferroic TbMnO_3.
At low temperatures TbMnO_3 demonstrates an incommensurate spiral ordering of Mn spins which is accompanied by appearance of spontaneous electric polarization driven by applied magnetic field. The establishment of such spin ordering is usually described within the framework of a Heisenberg model with competing nearestneighbor and nextnearestneighbor exchange interactions. However, our theoretical estimations of these interactions by abinitio calculations demonstrate a clear deviation from Heisenberg model.
We consider first the coupling between magnetic and orbital orderings as a main source of nonHeisenberg behavior in TbMnO_3, but conclude that it does not explain the observed deviation. We find that higher order exchange couplings should be taken into account for proper treatment of the magnetism in TbMnO_3.
Magnetoelectric monopolar ordering in solids
The formalism of the macroscopic magnetoelectric monopolization is developed and its relation to the magnetoelectric response is given[1]. Using firstprinciples calculations, we use two different strategies to calculate the monopolization: (i) By using a multipole expansion of the magnetization density in atomic spheres around magnetic sites, and (ii) by using a formalism inspired by the modern theory of electric polarization. As an example, results for a series of lithium transition metal compounds LiMPO4 (M = Co, Fe, Mn, Ni) are shown, which can show ferromonopolar and antiferromonopolar ordering.
[1] N. A. Spaldin et al., PRB 88, 094429 (2013)
Excess electrons in anatase: a hybrid DFT and RPA study
Anatase TiO2 is employed in a variety of fields, such as (photo)catalysis, sensors and solar cells. Many of the
proposed applications rely on charge transport phenomena, and a deep understanding of the anatase
electronic properties is therefore crucial. In particular, the behavior of excess electrons in the system is still a
matter of debate. While some studies describe highly localized states, small polarons, experiments
report high charge mobility, more compatible with a less localized nature of the excess electrons, sometimes
called large polarons.
Electrons in Anatase and Rutile display different properties. In this work, the
properties of excess electrons in anatase are obtained from hybrid DFT and RPA calculations, to shed light
on the geometry and the stability difference between localized and delocalized electronic states with stateof
theart electronic structure methods.
In anatase, we find that the polaronic state, which localizes on a Ti site, induces a long range lattice
relaxation in the [100] and [010] directions. This distortion extends for almost 10 Å in the [100] and [010]
directions. To fully accommodate this relaxation and to yield realistic results, calculations must therefore
employ supercells of at least 4x4x1 unit cells. Hybrid density functionals predict energy differences between
localized and delocalized electrons (ΔElocdeloc) that strongly depend on the amount of HartreeFock
exchange (%HFX) employed. When the %HFX is tuned such that the fundamental band is well described,
the delocalized electronic state is more stable by 0.3 eV. This picture qualitatively changes if the hybrid DFT
orbitals and eigenvalues are used as an input for RPA calculations. RPA results for Anatase show that the
stability of the localized and delocalized states becomes very similar, slightly favoring the localized state, in
agreement with experiment. Moreover, we show that ΔElocdeloc as obtained from the RPA calculations is
distinctly less sensitive on %HFX used in the initial step of the RPA calculation.
Modelling of Mo behavior in selected melts: Molecular Dynamics
The work is focused on assessment of ADS fuel matrix materials (i.e. MgO and Mo) behavior in chloride (LiClKCl) and fluoride (LiFAlF3) melts. It summarizes available data on Mo speciation in molten chloride systems. These data will be used for theoretical modeling of chemical behavior of Mo and Mg.
For the investigation of the molybdenum behavior in molten salts different modelling approaches are being used: Thermodynamic modeling (TD), molecular dynamic modeling (MD) and DFT. At this stage Molecular Dynamics is used for the acquisition of the missing data on the structural, kinetic and thermodynamic properties of the KClLiCl melts and Mo behavior in KClLiCl melt. Preliminary MD simulations demonstrated tendency to increase the number density of Cl atoms near the Mo atoms. At the same time number density of K atoms tend to decrease in the neighborhood of Mo atoms. Currently Molecular Dynamics is also used for the direct simulation of Mo dissolution in LiClKCl melt. First results of MD calculations are presented and discussed.
Molecule substrate registry on hBN supported by Rh(111) and other metallic surfaces
The investigation of properties and processes at complex interfaces between metallic substrates and adsorbed molecular systems requires the design of reliable models and efficient computational tools.
Working in close collaboration with experimentalists, we are constantly challenged to reproduce and/or interpret the observed behaviours. The final goal is to acquire in depth knowledge of the studied systems such to lead to the development of new materials with tailored properties.
Modern nanotemplates based on hexagonal boron nitride or graphene grown on transition metals show potential for future applications, due to their outstanding mechanical, thermal and electronic properties. The mismatch between the lattice constant of the sp2 overlayer and the substrate produces modulated structures, which act as nanotemplates for selfassembly, electron confinement, or intercalation.
We apply scanning tunnelling microscopy (STM) and density functional theory to investigate the adsorption of molecules and the formation and dynamics of defects.
In particular, the siteselectivity of hBN/Rh(111) (nanomesh) for the adsorption of hexaiodocyclohexaphenylene (I6CHP) and H2phthalocyanine is discussed. In both cases, we observe the preferential absorption within the pore of the nanomesh and the preferential orientation with respect to the substrate. Advanced sampling techniques and tuned analysis tools lead to a better understanding of the interaction between adsorbate and substrate, which could be exploited in the development of new structure and process, as the production of graphene derivatives on metal supported insulators.
Reference:
[1] J. G. Diaz, Y. Ding, R. Koitz, A. P. Seitsonen, M. Iannuzzi, and J. Hutter, Theor Chem Acc 132 (2013)
[2] H. Ma, Y. Ding, M. Iannuzzi, T. Brugger, S. Berner, J. Hutter, J. Osterwalder, and T. Greber, Langmuir 28, 15246 (2012).
[3] H. Cun, M. Iannuzzi, A. Hemmi, S. Roth, J. Osterwalder, and T. Greber, ACS Nano (2013).
[4] T. Dienel, J. GomezDiaz, A. Seitsonen, R. Widmer, M. Iannuzzi, K. Radican, H. Sachdev, K. Müllen, J. Hutter, and O. Gröning, submitted.
[5] M. Iannuzzi, F. Tran, T. Dienel, R. Widmer, Y. Ding, J. Hutter, and O. Gröning, submitted.
Ultraviolet photoemission spectroscopies from Koopmanscompliant functionals
Recently, we introduced a novel class of functionals that impose a generalized Koopmans’ condition into DFT [1]. These functionals aim at restoring the piecewise linear behavior of the total energy as a function of fractional number of particles and provide accurate predictions for the ionization potentials and electron affinities of molecules, in close comparison with both experiments and results from manybody perturbation theory (GW). In particular, through a convenient approach for simulating ultraviolet photoemission spectra (UPS), we find that UPS computed with these functionals are in remarkable agreement with experimental results. In addition, this approach allows us to interpret the outcome of orbital tomography obtained within angularresolved photoemission spectroscopy (ARPES) techniques.
References:
[1] I. Dabo, A. Ferretti, N. Poilvert, Y. Li, N. Marzari, and M. Cococcioni, Physical Review B 82, 115121 (2010).
Polarization rotation in ferroelectric walls in lead titanate and PZT
Domain walls in ferroelectric oxides are quasitwodimensional objects separating areas of the crystal with two different directions of polarization. Recently, there has been increasing interest in these interfaces because they display very unique structural and electronic properties which differ significantly from bulk crystalline behavior. We report the presence of a strong Bloch polarization component at 180 degree ferroelectric domain walls in PbTiO3 and tetragonal lead zirconate titanate. This newly discovered 2dimensional ferroelectric phase is bistable and can be switched from lefthanded chiral state to a righthanded chiral state. The strength of polarization and barrier energy for switching can be tuned by the composition of PZT. These type of domain walls show an extremely high piezoelectric coefficient (e33) of 20 C/m2 in the case of PbTiO3
Pushing the limits of the full potential allelectron quantum simulations.
Fullpotential linearized augmented planewave (FPLAPW) method is considered to be the gold standard among the allelectron methods for the electronic structure calculations. Like most ‘band methods’ LAPW uses a finite energyindependent basis to convert the secondorder differential equation problem into the generalized eigenvalue problem. The LAPW method is implemented in freely available codes (Exciting, Elk, FLEUR) as well as in commercial code (WIEN2k) and several ‘in house’ codes. In this work we present an implementation of the LAPW method on distributed hybrid CPUGPU systems that allows us to turnaround highly accurate 1000+ atom allelectron quantum materials simulations on clusters with a few hundred nodes. Key to our implementation is a novel algorithm to solve the generalized eigenvalue problem for complex symmetric dense matrices on distributed multithreaded systems that have a hybrid node architecture. This new implementation makes possible the use of extremescale quantum simulations in materials search and design problems as they appear in the materials genome project.
Theoretical and experimental investigation of PdGa surfaces and their catalytic properties
PdGa is an intermetallic (IMC) compound that has shown remarkable catalytic properties for an important reaction in polyethylene production, namely the partial hydrogenation of acetylene to ethylene [1]. IMCs are amongst the most ingenious and innovative catalyst materials as they enable spatial separation of the catalytically active sites.
In order to explore the catalytic properties of PdGa, namely high stability, activity and selectivity, we adopt a combined theoretical and experimental approach. As experimental methods we use lowenergy electron diffraction (LEED) and highresolution scanning tunneling microscopy (STM). For theoretical investigation we use DFT based large scale ab initio calculations with the cp2k code [2].
Since the hydrogenation reaction happens at the surface of the catalyst, our first challenge is determining which particular surface terminations of PdGa are most likely involved in the catalytic process. To have well defined experimental and simulation conditions we consider single crystals.
In a preliminary work [3], the most stable terminations of PdGa(111) and PdGa(111) surfaces were determined in our laboratory combining LEED method, highresolution scanning tunneling microscopy and ab initio thermodynamics calculations.
To have a more detailed picture of the possible scenario for acetylene hydrogenation we are currently applying the same joint experimental and theoretical strategy to other PdGa terminations (e.g. PdGa(210)).
In parallel, by means of the Nudged Elastic Band method, we unravel the atomistic details of the aforementioned catalytic reaction on such different surfaces.
A next challenge will be to investigate the ability of PdGa surfaces in chiral recognition by adsorption (again through experiment and in silico) of prochiral molecules on PdGa(111) and PdGa(111) surfaces.
1. K. Kovnir, M. Armbrüster, D. Teschner, T. V. Venkov, F. C. Jentoft, A. KnopGericke, Y. Grin, R. Schlögl, Sci. Technol. Adv. Mater. 2007, 8, 420 – 427.
2. J. VandeVondele, M. Krack, F. Mohamed, M. Parrinello, T. Chassaing, J. Hutter, Comput. Phys. Commun. 2005, 167, 103 – 128.
3. J. Prinz, R. Gaspari, C. A. Pignedoli, J. Vogt, P. Gille, M. Armbrüster, H. Brune, O. Gröning, D. Passerone, and R. Widmer, Angew. Chem., Int. Ed. 51, 9339 (2012).
TiO2based photocatalysis for water reduction
Hydrogen production gains importance due to the energy demand of the world. It can be accomplished by photocatalysis that converts energy of sunlight into H2 by reducing H2O.[1] Among tested photocatalysts for water reduction, TiO2 appears to be a promising one because of its ease of preparation and stability.[2] However, TiO2 has to be modified by adding photosensitizers (to harvest UV photons) and/or metal centers (for the reduction of water) to decrease its large band gap (~3.1 eV).[3]
In this study, we aim to theoretically design an efficient TiO2based photocatalyst for hydrogen production by water reduction. To modify the band gap of TiO2 and increase its photocatalytic activity, pyridinebased molecules [4] are used as photosensitizers and cobalt and nickel atoms as metal centers. All calculations are carried out by employing density functional theory (DFT) as implemented in CP2K/QUICKSTEP package.[5] The factors playing an important role in designing water reduction photocatalysts such as preferential adsorption sites of photosensitizer and metal centers on the TiO2 surface, the mechanism of water reduction, possible intermediate products and energy barrier for hydrogen production are going to be discussed.
References
1. Henderson, M. A., A surface science perspective on photocatalysis. Surface Science Reports 2011, 66 (6–7), 185297.
2. Leng, W. H.; Barnes, P. R. F.; Juozapavicius, M.; O’Regan, B. C.; Durrant, J. R., Electron Diffusion Length in Mesoporous Nanocrystalline TiO2 Photoelectrodes during Water Oxidation. The Journal of Physical Chemistry Letters 2010, 1 (6), 967972.
3. Kamat, P. V., Manipulation of Charge Transfer Across Semiconductor Interface. A Criterion That Cannot Be Ignored in Photocatalyst Design. The Journal of Physical Chemistry Letters 2012, 3 (5), 663672.
4. Ogawa, S.; Uchida, T.; Uchiya, T.; Hirano, T.; Saburi, M.; Uchidac, Y., Lithium complexation of configurational isomers of tetraaza macrocycle containing 2,2[prime or minute]bipyridine. XRay molecular structure of the transisomer of a dibutyl dicyano macrocycle. Journal of the Chemical Society, Perkin Transactions 1 1990, (6), 16491653.
5. VandeVondele, J.; Krack, M.; Mohamed, F.; Parrinello, M.; Chassaing, T.; Hutter, J., Quickstep: Fast and accurate density functional calculations using a mixed Gaussian and plane waves approach. Computer Physics Communications 2005, 167 (2), 103128.

Abinitiosimulation of twodimensional networks on the surface of water
(Abstract)


Presenting author 
Ralph Koitz (University of Zurich)

Coauthors 
Marcella Iannuzzi (University of Zurich), Juerg Hutter (University of Zurich) 
Poster # 
MAT01 


Anisotropydriven enhancement of spincorrelations
(Abstract)


Presenting author 
Jakub Imriska (ETH Zurich)

Coauthors 
Lei Wang (ETH Zurich), Emanuel Gull (University of Michigan), Matthias Troyer (ETH Zurich) 
Poster # 
MAT02 


Calculation of local properties
(Abstract)


Presenting author 
Sandra Luber (University of Zurich)

Coauthors 
Marcella Iannuzzi (University of Zurich), Jürg Hutter (University of Zurich) 
Poster # 
MAT03 


Multiferroic aurivillius phases: the case of Bi5FeTi3O15 by Ab Initio
(Abstract)


Presenting author 
Yaël Birenbaum (ETH Zurich)

Coauthors 
Claude Ederer (ETH Zurich) 
Poster # 
MAT04 


The highthroughput infrastructure AiiDA and the study of local polarization in perovskites
(Abstract)


Presenting author 
Giovanni Pizzi (EPFL)

Coauthors 
Andrea Cepellotti (EPFL), Boris Kozinsky (Bosch RTC, Cambridge, USA), Marco Fornari (Central Michigan University, USA), Nicola Marzari (EPFL) 
Poster # 
MAT05 


First principles study of the electrocaloric effect in strained BaTiO3
(Abstract)


Presenting author 
Madhura Marathe (ETH Zurich)

Coauthors 
Claude Ederer (ETH Zurich) 
Poster # 
MAT06 


Firstprinciples Fermi surface characterization of hole doped PbTe
(Abstract)


Presenting author 
Boris Sangiorgio (ETH Zurich)

Coauthors 
Michael Fechner (ETH Zurich), Nicola Spaldin (ETH Zurich) 
Poster # 
MAT07 


Firstprinciples simulation of electron transport in realistically large nanoelectronic devices
(Abstract)


Presenting author 
Mohammad Hossein BaniHashemian (ETH Zurich)

Coauthors 
Sascha Brück (ETH Zurich), Mathieu Luisier (ETH Zurich), Joost VandeVondele (ETH Zurich) 
Poster # 
MAT08 


Linear scaling Ehrenfest molecular dynamics
(Abstract)


Presenting author 
Samuel Andermatt (ETH Zurich)

Coauthors 
Florian Schiffmann (ETH Zurich), Joost VandeVondele (ETH Zurich) 
Poster # 
MAT09 


Local density fitting within a Gaussian and plane waves approach
(Abstract)


Presenting author 
Dorothea Golze (University of Zurich)

Coauthors 
Marcella Iannuzzi (University of Zurich), Juerg Hutter (University of Zurich) 
Poster # 
MAT10 


Magnetic properties of multiferroic TbMnO_3
(Abstract)


Presenting author 
Natalya Fedorova (ETH Zurich)

Coauthors 
Andrea Scaramucci (ETH Zurich), Claude Ederer (ETH Zurich), Nicola Spaldin (ETH Zurich) 
Poster # 
MAT11 


Magnetoelectric monopolar ordering in solids
(Abstract)


Presenting author 
Florian Thöle (ETH Zurich)

Coauthors 
Michael Fechner (ETH Zurich), Nicola Spaldin (ETH Zurich) 
Poster # 
MAT12 


Excess electrons in anatase: a hybrid DFT and RPA study
(Abstract)


Presenting author 
Clelia Spreafico (ETH Zurich)

Coauthors 
Joost VandeVondele (ETH Zurich) 
Poster # 
MAT13 


Modelling of Mo behavior in selected melts: Molecular Dynamics
(Abstract)


Presenting author 
Sergii Nichenko (Paul Scherrer Institut)

Coauthors 
Marco Streit (Paul Scherrer Institute) 
Poster # 
MAT14 


Molecule substrate registry on hBN supported by Rh(111) and other metallic surfaces
(Abstract)


Presenting author 
Marcella Iannuzzi (University of Zurich)

Coauthors 
Ari Seitsonen (University of Zurich), Jürg Hutter (University of Zurich) 
Poster # 
MAT15 


Ultraviolet photoemission spectroscopies from Koopmanscompliant functionals
(Abstract)


Presenting author 
Ngoc Linh Nguyen (EPFL)

Coauthors 
Giovanni Borghi (EPFL) , Andrea Ferretti (CNR–Istituto Nanoscienze, Italy), Ismaila Dabo (Pennsylvania State University, USA), Nicola Marzari (EPFL) 
Poster # 
MAT16 


Polarization rotation in ferroelectric walls in lead titanate and PZT
(Abstract)


Presenting author 
Anand Chandrasekaran (EPFL)

Coauthors 
Dragan Damjanovic (EPFL), Nava Setter (EPFL), Nicola Marzari (EPFL) 
Poster # 
MAT17 


Pushing the limits of the full potential allelectron quantum simulations.
(Abstract)


Presenting author 
Anton Kozhevnikov (ETH Zurich and CSCS)

Coauthors 
Azzam Haidar (University of Tennessee, USA), Stan Tomov (University of Tennessee, USA), Thomas Schulthess (ETH Zurich) 
Poster # 
MAT18 


Theoretical and experimental investigation of PdGa surfaces and their catalytic properties
(Abstract)


Presenting author 
A. Yakutovich (EMPA)

Coauthors 
Carlo A. Pignedoli (EMPA), Jan Prinz (EMPA), Roland Widmer (EMPA), Daniele Passerone (EMPA) 
Poster # 
MAT19 


TiO2based photocatalysis for water reduction
(Abstract)


Presenting author 
Yeliz Gurdal (University of Zurich)

Coauthors 
Sandra Luber (University of Zurich), Marcella Iannuzzi (University of Zurich), Jurg Hutter (University of Zurich) 
Poster # 
MAT20 
