Browsing by Author "Krasheninnikov, Arkady V."
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Item Advances in nanocarbon composite materials(2018-01-03) Malik, Sharali; Krasheninnikov, Arkady V.; Marchesan, Silvia; Karlsruhe Institute of Technology; Department of Applied Physics; University of TriesteItem Alkali metals inside bi-layer graphene and MoS2: Insights from first-principles calculations(Elsevier Science B.V., 2020-09) Chepkasov, Ilya V.; Ghorbani-Asl, Mahdi; Popov, Zakhar I.; Smet, Jurgen H.; Krasheninnikov, Arkady V.; Department of Applied Physics; Helmholtz-Zentrum Dresden-Rossendorf; National University of Science and Technology; Max Planck Institute for Solid State ResearchContrary to a wide-spread belief that alkali metal (AM) atoms intercalated into layered materials form single-layer structures only, recent experiments [Nature 564 (2018) 234] showed that multi-layer configurations of lithium are possible in bi-layer graphene. Using state-of-the-art first-principles calculations, we systematically study the intercalation energetics for various AMs (Li, Na, K, Rb, Cs) in bi-layer graphene and MoS2. We demonstrate that for bi-layer graphene as host the formation energy of multi-layer structures is negative for K, Rb and Cs and only slightly positive for both Li and Na. In view of the previous experimental data on lithium, a multi-layer of Na might therefore form, while it is well-known that single-layers of Na in graphitic hosts are energetically very unfavorable. In MoS2, multi-layer structures are considerably higher in energy than the single-layer ones, but the formation of the former can still occur, especially for the AMs with the lowest electro-negativity. To rationalize the results, we assess the charge transfer from the intercalants to the host material and analyze the interplay between the ionic and covalent bonding of AM and host atoms. While our theoretical effort primarily focuses on the fundamental aspects of AM intercalation, our findings may stimulate experimental work addressing multi-layer intercalation to maximize the capacity of anode materials in AM ion batteries.Item Atomic scale interface design and characterisation(2015) Bittencourt, Carla; Ewels, Chris; Krasheninnikov, Arkady V.; Department of Applied Physics; Universite de Mons; Université de NantesItem Atomistic simulations of defect production in monolayer and bulk hexagonal boron nitride under low-and high-fluence ion irradiation(Multidisciplinary Digital Publishing Institute (MDPI), 2021-05) Ghaderzadeh, Sadegh; Kretschmer, Silvan; Ghorbani-Asl, Mahdi; Hlawacek, Gregor; Krasheninnikov, Arkady V.; Department of Applied Physics; Helmholtz-Zentrum Dresden-RossendorfControlled production of defects in hexagonal boron nitride (h-BN) through ion irradiation has recently been demonstrated to be an effective tool for adding new functionalities to this material, such as single-photon generation, and for developing optical quantum applications. Using analytical potential molecular dynamics, we study the mechanisms of vacancy creation in single-and multi-layer h-BN under low-and high-fluence ion irradiation. Our results quantify the densities of defects produced by noble gas ions in a wide range of ion energies and elucidate the types and distribution of defects in the target. The simulation data can directly be used to guide the experiment aimed at the creation of defects of particular types in h-BN targets for single-photon emission, spin-selective optical transitions and other applications by using beams of energetic ions.Item Atomistic Simulations of Defects Production under Ion Irradiation in Epitaxial Graphene on SiC(WILEY-VCH VERLAG, 2023-03) Jain, Mitisha; Kretschmer, Silvan; Höflich, Katja; Lopes, Joao Marcelo Jordao; Krasheninnikov, Arkady V.; Department of Applied Physics; Soft Matter and Wetting; Helmholtz-Zentrum Dresden-Rossendorf; Helmholtz Centre Berlin for Materials and Energy; Forschungsverbund Berlin e.V.Using first-principles and analytical potential atomistic simulations, production of defects in epitaxial graphene (EG) on SiC upon ion irradiation for ion types and energies accessible in helium-ion microscope is studied. Graphene-SiC systems consisting of the buffer (zero) graphene layer and SiC substrate, as well as one (monolayer) and two (bilayer) additional graphene layers, are focused on. The probabilities for single, double, and more complex vacancies to appear upon impacts of energetic ions in each graphene layer as functions of He- and Ne-ion energies are calculated and the data are compared with those obtained for free-standing graphene. The results indicate that the role of the substrate is minimal for He-ion irradiation with energies above 5 keV, which can be associated with a low sputtering yield from this system upon ion irradiation, as compared with the common Si/SiO2 substrate. In contrast, SiC substrate has a significant effect on defect production upon Ne-ion irradiation. The results can serve as a guide to the experiments on ion irradiation of EG to choose the optimum ion beam parameters for defect-mediated engineering of such systems, for example, for creating nucleation centers to grow other 2D materials, such as h-BN, on top of the irradiated EG.Item Berseneva, Krasheninnikov, and Nieminen Reply(American Physical Society (APS), 2011) Berseneva, Natalia; Krasheninnikov, Arkady V.; Nieminen, Risto M.; Teknillisen fysiikan laitos; Department of Applied Physics; Perustieteiden korkeakoulu; School of ScienceA Reply to the Comment by Bing Huang and Su-Huai Wei.Item Boosting the Electrocatalytic Conversion of Nitrogen to Ammonia on Metal-Phthalocyanine-Based Two-Dimensional Conjugated Covalent Organic Frameworks(AMERICAN CHEMICAL SOCIETY, 2021-12-01) Zhong, Haixia; Wang, Mingchao; Ghorbani-Asl, Mahdi; Zhang, Jichao; Ly, Khoa Hoang; Liao, Zhongquan; Chen, Guangbo; Wei, Yidan; Biswal, Bishnu P.; Zschech, Ehrenfried; Weidinger, Inez M.; Krasheninnikov, Arkady V.; Dong, Renhao; Feng, Xinliang; Department of Applied Physics; Technische Universität Dresden; Helmholtz-Zentrum Dresden-Rossendorf; Shanghai Advanced Research Institute; Fraunhofer Institute for Ceramic Technologies and Systems; National Institute of Science Education and ResearchThe electrochemical N2 reduction reaction (NRR) under ambient conditions is attractive in replacing the current Haber-Bosch process toward sustainable ammonia production. Metal-heteroatom-doped carbon-rich materials have emerged as the most promising NRR electrocatalysts. However, simultaneously boosting their NRR activity and selectivity remains a grand challenge, while the principle for precisely tailoring the active sites has been elusive. Herein, we report the first case of crystalline two-dimensional conjugated covalent organic frameworks (2D c-COFs) incorporated with M-N4-C centers as novel, defined, and effective catalysts, achieving simultaneously enhanced activity and selectivity of electrocatalytic NRR to ammonia. Such 2D c-COFs are synthesized based on metal-phthalocyanine (M = Fe, Co, Ni, Mn, Zn, and Cu) and pyrene units bonded by pyrazine linkages. Significantly, the 2D c-COFs with Fe-N4-C center exhibit higher ammonia yield rate (33.6 μg h-1 mgcat-1) and Faradaic efficiency (FE, 31.9%) at -0.1 V vs reversible hydrogen electrode than those with other M-N4-C centers, making them among the best NRR electrocatalysts (yield rate >30 μg h-1 mgcat-1 and FE > 30%). In situ X-ray absorption spectroscopy, Raman spectroelectrochemistry, and theoretical calculations unveil that Fe-N4-C centers act as catalytic sites. They show a unique electronic structure with localized electronic states at Fermi level, allowing for stronger interaction with N2 and thus faster N2 activation and NRR kinetics than other M-N4-C centers. Our work opens the possibility of developing metal-nitrogen-doped carbon-rich 2D c-COFs as superior NRR electrocatalyst and provides an atomic understanding of the NRR process on M-Nx-C based electrocatalysts for designing high-performance NRR catalysts.Item Bound and free self-interstitial defects in graphite and bilayer graphene: A computational study(American Physical Society (APS), 2011) Gulans, Andris; Krasheninnikov, Arkady V.; Puska, Martti J.; Nieminen, Risto M.; Teknillisen fysiikan laitos; Department of Applied Physics; Perustieteiden korkeakoulu; School of ScienceThe role of self-interstitials in the response of layered carbon materials such as graphite, bilayer graphene and multiwalled carbon nanotubes to irradiation has long remained a puzzle. Using density-functional-theory methods with an exchange and correlation functional which takes into account the interlayer van der Waals interaction in these systems without any material-specific empirical parameters, we study the energetics and migration of single- and di-interstitials in graphite and bilayer graphene. We show that two classes of interstitials, “bound” and “free,” can coexist. The latter are mobile at room and lower temperatures, which explains the experimental data and reconciles them with the results of atomistic simulations. Our results shed light on the behavior of graphite and carbon nanotubes under irradiation and have implications for irradiation-mediated processing of bilayer graphene.Item Catalytic Activity of Defect-Engineered Transition Me tal Dichalcogenides Mapped with Atomic-Scale Precision by Electrochemical Scanning Tunneling Microscopy(AMERICAN CHEMICAL SOCIETY, 2023-01-16) Lunardon, Marco; Kosmala, Tomasz; Ghorbani-Asl, Mahdi; Krasheninnikov, Arkady V.; Kolekar, Sadhu; Durante, Christian; Batzill, Matthias; Agnoli, Stefano; Granozzi, Gaetano; Department of Applied Physics; Soft Matter and Wetting; University of Padova; Helmholtz-Zentrum Dresden-Rossendorf; University of South FloridaUnraveling structure-activity relationships is a key objective of catalysis. Unfortunately, the intrinsic complexity and structural heterogeneity of materials stand in the way of this goal, mainly because the activity measurements are area-averaged and therefore contain information coming from different surface sites. This limitation can be surpassed by the analysis of the noise in the current of electrochemical scanning tunneling microscopy (EC-STM). Herein, we apply this strategy to investigate the catalytic activity toward the hydrogen evolution reaction of monolayer films of MoSe2. Thanks to atomically resolved potentiodynamic experiments, we can evaluate individually the catalytic activity of the MoSe2 basal plane, selenium vacancies, and different point defects produced by the intersections of metallic twin boundaries. The activity trend deduced by EC-STM is independently confirmed by density functional theory calculations, which also indicate that, on the metallic twin boundary crossings, the hydrogen adsorption energy is almost thermoneutral. The micro- and macroscopic measurements are combined to extract the turnover frequency of different sites, obtaining for the most active ones a value of 30 s-1 at −136 mV vs RHE.Item Channeling effects in gold nanoclusters under He ion irradiation: Insights from molecular dynamics simulations(IOP PUBLISHING LTD, 2020-01-17) Ghaderzadeh, Sadegh; Ghorbani-Asl, Mahdi; Kretschmer, Silvan; Hlawacek, Gregor; Krasheninnikov, Arkady V.; Department of Applied Physics; Helmholtz-Zentrum Dresden-RossendorfThe interpretation of helium ion microscopy (HIM) images of crystalline metal clusters requires microscopic understanding of the effects of He ion irradiation on the system, including energy deposition and associated heating, as well as channeling patterns. While channeling in bulk metals has been studied at length, there is no quantitative data for small clusters. We carry out molecular dynamics simulations to investigate the behavior of gold nanoparticles with diameters of 5-15 nm under 30 keV He ion irradiation. We show that impacts of the ions can give rise to substantial heating of the clusters through deposition of energy into electronic degrees of freedom, but it does not affect channeling, as clusters cool down between consecutive impact of the ions under typical imaging conditions. At the same time, high temperatures and small cluster sizes should give rise to fast annealing of defects so that the system remains crystalline. Our results show that ion-channeling occurs not only in the principal low-index, but also in the intermediate directions. The strengths of different channels are specified, and their correlations with sputtering-yield and damage production is discussed, along with size-dependence of these properties. The effects of planar defects, such as stacking faults on channeling were also investigated. Finally, we discuss the implications of our results for the analysis of HIM images of metal clusters.Item Charge-exchange-dependent energy loss of H and He in freestanding monolayers of graphene and MoS2(American Physical Society, 2023-12) Niggas, Anna; Fischer, Lukas; Kretschmer, Silvan; Werl, Matthias; Biber, Herbert; Speckmann, Carsten; Mcevoy, Niall; Kotakoski, Jani; Aumayr, Friedrich; Krasheninnikov, Arkady V.; Wilhelm, Richard A.; Department of Applied Physics; Soft Matter and Wetting; Vienna University of Technology; Helmholtz-Zentrum Dresden-Rossendorf; University of Vienna; Trinity College DublinWe study the energy loss of helium and hydrogen ions after transmission through monolayers of graphene and MoS2 and compare experimental results with different computational approaches. We find a systematically higher energy loss in experiments compared to simulations by up to a factor of 2. Additionally, our results show that neutralization processes of the particles increase the kinetic energy loss, a contribution generally not included in any computational approach.Item Charged Point Defects in the Flatland: Accurate Formation Energy Calculations in Two-Dimensional Materials(American Physical Society (APS), 2014) Komsa, Hannu-Pekka; Berseneva, Natalia; Krasheninnikov, Arkady V.; Nieminen, Risto M.; Teknillisen fysiikan laitos; Department of Applied Physics; Perustieteiden korkeakoulu; School of ScienceImpurities and defects frequently govern materials properties, with the most prominent example being the doping of bulk semiconductors where a minute amount of foreign atoms can be responsible for the operation of the electronic devices. Several computational schemes based on a supercell approach have been developed to get insights into types and equilibrium concentrations of point defects, which successfully work in bulk materials. Here, we show that many of these schemes cannot directly be applied to two-dimensional (2D) systems, as formation energies of charged point defects are dominated by large spurious electrostatic interactions between defects in inhomogeneous environments. We suggest two approaches that solve this problem and give accurate formation energies of charged defects in 2D systems in the dilute limit. Our methods, which are applicable to all kinds of charged defects in any 2D system, are benchmarked for impurities in technologically important h-BN and MoS2 2D materials, and they are found to perform equally well for substitutional and adatom impurities.Item Chemical Vapor Deposition of High-Optical-Quality Large-Area Monolayer Janus Transition Metal Dichalcogenides(WILEY-VCH VERLAG, 2022-09-22) Gan, Ziyang; Paradisanos, Ioannis; Estrada-Real, Ana; Picker, Julian; Najafidehaghani, Emad; Davies, Francis; Neumann, Christof; Robert, Cedric; Wiecha, Peter; Watanabe, Kenji; Taniguchi, Takashi; Marie, Xavier; Biskupek, Johannes; Mundszinger, Manuel; Leiter, Robert; Kaiser, Ute; Krasheninnikov, Arkady V.; Urbaszek, Bernhard; George, Antony; Turchanin, Andrey; Department of Applied Physics; Soft Matter and Wetting; Friedrich Schiller University Jena; Université Paul Sabatier Toulouse III; Helmholtz-Zentrum Dresden-Rossendorf; IRAP; National Institute for Materials Science; Ulm UniversityOne-pot chemical vapor deposition (CVD) growth of large-area Janus SeMoS monolayers is reported, with the asymmetric top (Se) and bottom (S) chalcogen atomic planes with respect to the central transition metal (Mo) atoms. The formation of these 2D semiconductor monolayers takes place upon the thermodynamic-equilibrium-driven exchange of the bottom Se atoms of the initially grown MoSe2 single crystals on gold foils with S atoms. The growth process is characterized by complementary experimental techniques including Raman and X-ray photoelectron spectroscopy, transmission electron microscopy, and the growth mechanisms are rationalized by first principle calculations. The remarkably high optical quality of the synthesized Janus monolayers is demonstrated by optical and magneto-optical measurements which reveal the strong exciton–phonon coupling and enable an exciton g-factor of −3.3.Item Chlorine doping of MoSe2flakes by ion implantation(ROYAL SOC CHEMISTRY, 2021-03-21) Prucnal, Slawomir; Hashemi, Arsalan; Ghorbani-Asl, Mahdi; Hübner, René; Duan, Juanmei; Wei, Yidan; Sharma, Divanshu; Zahn, Dietrich R.T.; Ziegenrücker, René; Kentsch, Ulrich; Krasheninnikov, Arkady V.; Helm, Manfred; Zhou, Shengqiang; Helmholtz-Zentrum Dresden-Rossendorf EV; Department of Applied Physics; Chemnitz University of TechnologyThe efficient integration of transition metal dichalcogenides (TMDs) into the current electronic device technology requires mastering the techniques of effective tuning of their optoelectronic properties. Specifically, controllable doping is essential. For conventional bulk semiconductors, ion implantation is the most developed method offering stable and tunable doping. In this work, we demonstrate n-type doping in MoSe2 flakes realized by low-energy ion implantation of Cl+ ions followed by millisecond-range flash lamp annealing (FLA). We further show that FLA for 3 ms with a peak temperature of about 1000 °C is enough to recrystallize implanted MoSe2. The Cl distribution in few-layer-thick MoSe2 is measured by secondary ion mass spectrometry. An increase in the electron concentration with increasing Cl fluence is determined from the softening and red shift of the Raman-active A1g phonon mode due to the Fano effect. The electrical measurements confirm the n-type doping of Cl-implanted MoSe2. A comparison of the results of our density functional theory calculations and experimental temperature-dependent micro-Raman spectroscopy data indicates that Cl atoms are incorporated into the atomic network of MoSe2 as substitutional donor impurities. This journal isItem Controlling Stoichiometry in Ultrathin van der Waals Films(AMERICAN CHEMICAL SOCIETY, 2022-06-28) Lasek, Kinga; Ghorbani-Asl, Mahdi; Pathirage, Vimukthi; Krasheninnikov, Arkady V.; Batzill, Matthias; University of South Florida; Helmholtz-Zentrum Dresden-Rossendorf EV; Department of Applied PhysicsThe platinum-tellurium phase diagram exhibits various (meta)stable van der Waals (vdW) materials that can be constructed by stacking PtTe2 and Pt2Te2 layers. Monophase PtTe2, being the thermodynamically most stable compound, can readily be grown as thin films. Obtaining the other phases (Pt2Te3, Pt3Te4, Pt2Te2), especially in their ultimate thin form, is significantly more challenging. We show that PtTe2 thin films can be transformed by vacuum annealing-induced Te-loss into Pt3Te4- and Pt2Te2-bilayers. These transformations are characterized by scanning tunneling microscopy and X-ray and angle resolved photoemission spectroscopy. Once Pt3Te4 is formed, it is thermally stable up to 350°C. To transform Pt3Te4 into Pt2Te2, a higher annealing temperature of 400°C is required. The experiments combined with density functional theory calculations provide insights into these transformation mechanisms and show that a combination of the thermodynamic preference of Pt3Te4 over a phase segregation into PtTe2 and Pt2Te2 and an increase in the Te-vacancy formation energy for Pt3Te4 compared to the starting PtTe2 material is critical to stabilize the Pt3Te4 bilayer. To desorb more tellurium from Pt3Te4 and transform the material into Pt2Te2, a higher Te-vacancy formation energy has to be overcome by raising the temperature. Interestingly, bilayer Pt2Te2 can be retellurized by exposure to Te-vapor. This causes the selective transformation of the topmost Pt2Te2 layer into two layers of PtTe2, and consequently the synthesis of e Pt2Te3. Thus, all known Pt-telluride vdW compounds can be obtained in their ultrathin form by carefully controlling the stoichiometry of the material.Item Creation of paired electron states in the gap of semiconducting carbon nanotubes by correlated hydrogen adsorption(IOP Publishing, 2007) Buchs, Gilles; Krasheninnikov, Arkady V.; Ruffieux, Pascal; Gröning, Pierangelo; Foster, Adam S.; Nieminen, Risto M.; Gröning, Oliver; Teknillisen fysiikan laitos; Department of Applied Physics; Perustieteiden korkeakoulu; School of ScienceThe specific, local modification of the electronic structure of carbon nanomaterials is as important for novel electronic device fabrication as the doping in the case of silicon-based electronics. Here, we report low temperature scanning tunneling microscopy and spectroscopy study of semiconducting carbon nanotubes subjected to hydrogen-plasma treatment. We show that plasma treatment mostly results in the creation of paired electronic states in the nanotube band gap. Combined with extensive first-principle simulations, our results provide direct evidence that these states originate from correlated chemisorption of hydrogen adatoms on the tube surface. The energy splitting of the paired states is governed by the adatom–adatom interaction, so that controlled hydrogenation can be used for engineering the local electronic structure of nanotubes and other sp2-bonded nanocarbon systems.Item Data-Driven Quest for Two-Dimensional Non-van der Waals Materials(AMERICAN CHEMICAL SOCIETY, 2022-02-09) Friedrich, Rico; Ghorbani-Asl, Mahdi; Curtarolo, Stefano; Krasheninnikov, Arkady V.; Department of Applied Physics; Helmholtz-Zentrum Dresden-Rossendorf; Duke UniversityTwo-dimensional (2D) materials are frequently associated with the sheets forming bulk layered compounds bonded by van der Waals (vdW) forces. The anisotropy and weak interaction between the sheets have also been the main criteria in the computational search for new 2D systems, predicting ∼2000 exfoliable compounds. However, some representatives of a new type of non-vdW 2D systems, without layered 3D analogues, were recently manufactured. For this novel materials class, data-driven design principles are still missing. Here, we outline a set of 8 binary and 20 ternary candidates by filtering the AFLOW-ICSD database according to structural prototypes. The oxidation state of the surface cations regulates the exfoliation energy with low oxidation numbers leading to weak bonding─a useful descriptor to obtain novel 2D materials also providing clear guidelines for experiments. A vast range of appealing electronic, optical, and magnetic properties make the candidates attractive for various applications and particularly spintronics.Item Defect Agglomeration and Electron-Beam-Induced Local-Phase Transformations in Single-Layer MoTe2(AMERICAN CHEMICAL SOCIETY, 2021-06-24) Köster, Janis; Ghorbani-Asl, Mahdi; Komsa, Hannu Pekka; Lehnert, Tibor; Kretschmer, Silvan; Krasheninnikov, Arkady V.; Kaiser, Ute; Ulm University; Helmholtz-Zentrum Dresden-Rossendorf EV; Department of Applied PhysicsAtom migrations in single-layer 1H-MoTe2 are studied with Cc/Cs-corrected high-resolution transmission electron microscopy at an electron energy of 40 keV using the electron beam simultaneously for material modification and imaging. After creating tellurium vacancies and vacancy lines, we observe their migration pathways across the lattice. Furthermore, we analyze phase transformations from the 1H- to the 1T′-phase associated with the strain induced due to the formation of Te vacancy lines. Combining the experimental data with the results of first-principles calculations, we explain the energetics and driving forces of point- and line-defect migrations and the phase transformations due to an interplay of electron-beam-induced energy input, atom ejection, and strain spread. Our results enhance the understanding of defect dynamics in 2D transition metal dichalcogenides, which should facilitate tailoring their local optical and electronic properties.Item Edge and Point-Defect Induced Electronic and Magnetic Properties in Monolayer PtSe2(WILEY-VCH VERLAG, 2022-05-02) Li, Jingfeng; Joseph, Thomas; Ghorbani-Asl, Mahdi; Kolekar, Sadhu; Krasheninnikov, Arkady V.; Batzill, Matthias; University of South Florida; Helmholtz-Zentrum Dresden-Rossendorf EV; Department of Applied PhysicsEdges and point defects in layered dichalcogenides are important for tuning their electronic and magnetic properties. By combining scanning tunneling microscopy (STM) with density functional theory (DFT), the electronic structure of edges and point defects in 2D-PtSe2 are investigated where the 1.8 eV bandgap of monolayer PtSe2 facilitates the detailed characterization of defect-induced gap states by STM. The stoichiometric zigzag edge terminations are found to be energetically favored. STM and DFT show that these edges exhibit metallic 1D states with spin polarized bands. Various native point defects in PtSe2 are also characterized by STM. A comparison of the experiment with simulated images enables identification of Se-vacancies, Pt-vacancies, and Se-antisites as the dominant defects in PtSe2. In contrast to Se- or Pt-vacancies, the Se-antisites are almost devoid of gap states. Pt-vacancies exhibit defect induced states that are spin polarized, emphasizing their importance for inducing magnetism in PtSe2. The atomic-scale insights into defect-induced electronic states in monolayer PtSe2 provide the fundamental underpinning for defect engineering of PtSe2-monolayers and the newly identified spin-polarized edge states offer prospects for engineering magnetic properties in PtSe2 nanoribbons.Item Efficient Calculation of the Lattice Thermal Conductivity by Atomistic Simulations with Ab Initio Accuracy(WILEY-V C H VERLAG GMBH, 2022-02) Brorsson, Joakim; Hashemi, Arsalan; Fan, Zheyong; Fransson, Erik; Eriksson, Fredrik; Ala-Nissila, Tapio; Krasheninnikov, Arkady V.; Komsa, Hannu Pekka; Erhart, Paul; Department of Applied Physics; Multiscale Statistical and Quantum Physics; Chalmers University of TechnologyHigh-order force constant expansions can provide accurate representations of the potential energy surface relevant to vibrational motion. They can be efficiently parametrized using quantum mechanical calculations and subsequently sampled at a fraction of the cost of the underlying reference calculations. Here, force constant expansions are combined via the hiphive package with GPU-accelerated molecular dynamics simulations via the GPUMD package to obtain an accurate, transferable, and efficient approach for sampling the dynamical properties of materials. The performance of this methodology is demonstrated by applying it both to materials with very low thermal conductivity (Ba8Ga16Ge30, SnSe) and a material with a relatively high lattice thermal conductivity (monolayer-MoS2). These cases cover both situations with weak (monolayer-MoS2, SnSe) and strong (Ba8Ga16Ge30) pho renormalization. The simulations also enable to access complementary information such as the spectral thermal conductivity, which allows to discriminate the contribution by different phonon modes while accounting for scattering to all orders. The software packages described here are made available to the scientific community as free and open-source software in order to encourage the more widespread use of these techniques as well as their evolution through continuous and collaborative development.
