TY - CONF
A1 - Bustamante, Joana
A1 - Naik, Aakash
A1 - Ertural, Christina
A1 - Ueltzen, Katharina
A1 - George, Janine
T1 - Thermodynamic and Thermoelectric Properties of the Canfieldite, (Ag8SnS6 ), in the Quasi-Harmonic Approximation
N2 - Argyrodite-type materials have lately sparked a lot of research interest due to their thermoelectric properties.One promising candidate is canfieldite (Ag8SnS6), which has a Pna21 orthorhombic crystal structure at room temperature (RT). Recently, a new low-temperature (LT) phase transition of canfieldite at 120K has been found. Here, we investigate structural, vibrational and thermodynamic properties of Ag8SnS6 at room- and low-temperature employing density functional theory (DFT) and lattice dynamics computations. Thermal properties calculations were based on the quasi-harmonic approximation (QHA) as implemented in phonopy. We achieve good agreement with experiments. Thermal properties such as the constant-pressure heat capacity (Cp) and thermal conductivity are very close to experimental measurements. Furthermore, we compared RT and LT Ag8SnS6 Grüneisen parameters with argyrodites analogues, Ag8XS6 (X = Sn, Si, Ge), to arrive at an improved
T2 - 16th International conference on materials chemistry (MC16)
CY - Dublin, Ireland
DA - 03.07.2023
KW - Thermoelectric materials
KW - DFT
KW - QHA
KW - Grüneisen parameter
PY - 2023
AN - OPUS4-57887
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - INPR
A1 - Ganose, Alex
A1 - Sahasrabuddhe, Hrushikesh
A1 - Asta, Mark
A1 - Beck, Kevin
A1 - Biswas, Tathagata
A1 - Bonkowski, Alexander
A1 - Bustamante, Joana
A1 - Chen, Xin
A1 - Chiang, Yuan
A1 - Chrzan, Daryl
A1 - Clary, Jacob
A1 - Cohen, Orion
A1 - Ertural, Christina
A1 - George, Janine
A1 - Gallant, Max
A1 - George, Janine
A1 - Gerits, Sophie
A1 - Goodall, Rhys
A1 - Guha, Rishabh
A1 - Hautier, Geoffroy
A1 - Horton, Matthew
A1 - Kaplan, Aaron
A1 - Kingsbury, Ryan
A1 - Kuner, Matthew
A1 - Li, Bryant
A1 - Linn, Xavier
A1 - McDermott, Matthew
A1 - Rohith Srinivaas Mohanakrishnan,
A1 - Naik, Aakash
A1 - Neaton, Jeffrey
A1 - Persson, Kristin
A1 - Petretto, Guido
A1 - Purcell, Thomas
A1 - Ricci, Francesco
A1 - Rich, Benjamin
A1 - Riebesell, Janosh
A1 - Rignanese, Gian-Marco
A1 - Rosen, Andrew
A1 - Scheffler, Matthias
A1 - Schmidt, Jonathan
A1 - Shen, Jimmy-Xuan
A1 - Sobolev, Andrei
A1 - Sundararaman, Ravishankar
A1 - Tezak, Cooper
A1 - Trinquet, Victor
A1 - Varley, Joel
A1 - Vigil-Fowler, Derek
A1 - Wang, Duo
A1 - Waroquiers, David
A1 - Wen, Mingjian
A1 - Yang, Han
A1 - Zheng, Hui
A1 - Zheng, Jiongzhi
A1 - Zhu, Zhuoying
A1 - Jain, Anubhav
T1 - Atomate2: Modular workflows for materials science
N2 - High-throughput density functional theory (DFT) calculations have become a vital element of computational materials science, enabling materials screening, property database generation, and training of “universal” machine learning models. While several software frameworks have emerged to support these computational efforts, new developments such as machine learned force fields have increased demands for more flexible and programmable workflow solutions. This manuscript introduces atomate2, a comprehensive evolution of our original atomate framework, designed to address existing limitations in computational materials research infrastructure. Key features include the support for multiple electronic structure packages and interoperability between them, along with generalizable workflows that can be written in an abstract form irrespective of the DFT package or machine learning force field used within them. Our hope is that atomate2’s improved usability and extensibility can reduce technical barriers for high-throughput research workflows and facilitate the rapid adoption of emerging methods in computational material science.
KW - Automation
KW - DFT
KW - Digitalisation
KW - Materials design
KW - Machine learning
KW - Machine learned interatomic potentials
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624487
DO - https://doi.org/10.26434/chemrxiv-2025-tcr5h
SN - 2573-2293
SP - 1
EP - 66
PB - American Chemical Society (ACS)
CY - Washington, D.C.
AN - OPUS4-62448
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ghata, Anupama
A1 - Bernges, Tim
A1 - Maus, Oliver
A1 - Wankmiller, Björn
A1 - Naik, Aakash
A1 - Bustamante, Joana
A1 - Gaultois, Michael W.
A1 - Delaire, Olivier
A1 - Hansen, Michael Ryan
A1 - George, Janine
A1 - Zeier, Wolfgang G.
T1 - Exploring the Thermal and Ionic Transport of Cu+ Conducting Argyrodite Cu7PSe6
N2 - AbstractUnderstanding the origin of low thermal conductivities in ionic conductors is essential for improving their thermoelectric efficiency, although accompanying high ionic conduction may present challenges for maintaining thermoelectric device integrity. This study investigates the thermal and ionic transport in Cu7PSe6, aiming to elucidate their fundamental origins and correlation with the structural and dynamic properties. Through a comprehensive approach including various characterization techniques and computational analyses, it is demonstrated that the low thermal conductivity in Cu7PSe6 arises from structural complexity, variations in bond strengths, and high lattice anharmonicity, leading to pronounced diffuson transport of heat and fast ionic conduction. It is found that upon increasing the temperature, the ionic conductivity increases significantly in Cu7PSe6, whereas the thermal conductivity remains nearly constant, revealing no direct correlation between ionic and thermal transport. This absence of direct influence suggests innovative design strategies in thermoelectric applications to enhance stability by diminishing ionic conduction, while maintaining low thermal conductivity, thereby linking the domains of solid‐state ionics and thermoelectrics. Thus, this study attempts to clarify the fundamental principles governing thermal and ionic transport in Cu+‐superionic conductors, similar to recent findings in Ag+ argyrodites.
KW - Thermoelectrics
KW - Phonons
KW - Chemically Complex Materials
KW - DFT
KW - Bonding Analysis
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608866
DO - https://doi.org/10.1002/aenm.202402039
SP - 1
EP - 9
PB - Wiley
AN - OPUS4-60886
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bustamante, Joana
A1 - Naik, Aakash
A1 - Ueltzen, Katharina
A1 - Ertural, Christina
A1 - George, Janine
T1 - Thermodynamic and Thermoelectric Properties of the Canfieldite, (Ag8SnS6 ), in the Quasi-Harmonic Approximation
N2 - Argyrodite-type materials have lately sparked a lot of research interest due to their thermoelectric properties. One promising candidate is canfieldite (Ag8SnS6), which has a Pna21 orthorhombic crystal structure at room temperature (RT). Recently, Slade group found a new low-temperature (LT) phase transition of canfieldite at 120K. Therefore, we investigate structural, vibrational and thermodynamic properties of Ag8SnS6 at room- and low-temperature employing density-functional theory (DFT) and lattice dynamics computations. Thermal properties calculations were based on the quasi-harmonic approximation (QHA) as implemented in phonopy. We achieve good agreement with experiments. Lattice parameters were overestimated by 2%, and thermal properties such as the constant-pressure heat capacity Cp are very close to experimental measurements. Our simulations also reveal a possible new phase transition at around 312 K. Furthermore, we compared RT and LT Ag8SnS6 Grüneisen parameters with some argyrodites analogues, Ag8TS6 (T = Si, Ge, Ti and Sn), finding a relationship between the anharmonicity and low thermal conductivity.
T2 - TDEP Summer School 2023 (TDEP2023: Finite-temperature and anharmonic response properties of solids in theory and practice)
CY - Linköping, Sweden
DA - 20.08.2023
KW - Thermoelectric materials
KW - DFT
KW - QHA
KW - Grüneisen parameter
PY - 2023
AN - OPUS4-58147
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Bustamante, Joana
A1 - Naik, Aakash
A1 - Ueltzen, Katharina
A1 - George, Janine
A1 - Ertural, Christina
T1 - Thermal Transport in Ag8TS6 (T= Si, Ge, Sn) Argyrodites: An Integrated Experimental, Quantum-Chemical, and Computational Modelling Study. DFT-part
N2 - This repository contains computational data supporting the manuscript titled *“Thermal Transport in Ag8TS6 (T= Si, Ge, Sn) Argyrodites: An Integrated Experimental, Quantum-Chemical, and Computational Modelling Study”* It includes raw data for vibrational properties, elastic properties and Bonding analysis.
KW - DFT
KW - QHA
KW - Lattice thermal conductivity
KW - Grüneisen parameter
PY - 2025
DO - https://doi.org/10.5281/zenodo.17399975
PB - Zenodo
CY - Geneva
AN - OPUS4-64671
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Bustamante, Joana
A1 - Naik, Aakash
A1 - Ueltzen, Katharina
A1 - Ertural, Christina
A1 - George, Janine
T1 - Thermal Transport in Ag8TS6 (T= Si, Ge, Sn) Argyrodites: An Integrated Experimental, Quantum-Chemical, and Computational Modelling Study.
N2 - This repository includes raw data for bonding analysis and lattice thermal conductivity using MLIP-MACE-MP03b, supporting the manuscript “Thermal Transport in Ag8TS6 (T= Si, Ge, Sn) Argyrodites: An Integrated Experimental, Quantum-Chemical, and Computational Modelling Study”
KW - DFT
KW - LOBSTER
KW - Lattice thermal conductivity
KW - MLIP
PY - 2025
DO - https://doi.org/10.5281/zenodo.17397456
PB - Zenodo
CY - Geneva
AN - OPUS4-64674
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Cope, Elana J.
A1 - Bustamante, Joana
A1 - Johnson, Zöe M.
A1 - Lancaster, Alicia
A1 - Gurunathan, Ramya
A1 - George, Janine
A1 - Agne, Matthias T.
T1 - Heat capacity estimation of complex materials for energy technologies
N2 - The control of heat in energy materials is one of the greatest current engineering challenges. Accurate estimations of heat capacity are key in creating and using materials safely and efficiently. Current models for heat capacity are often limited due to crude estimations of the phonon density of states, which is a key component of the thermodynamic definition of heat capacity. Utilization of a more detailed phonon density of states, which can easily be obtained from machine-learned algorithms, combined with dilation and electronic contributions, yields heat capacity estimations that are 29% better than the widely utilized Debye model and are comparable to state-of-the-art quantum mechanical calculations. The framework and necessary tools for heat capacity estimations demonstrated herein can be built into more detailed models and analyses, such as high-throughput characterization, transport models, or other thermodynamic assessments. Consequently, the so-called vibrational + dilation + electronic (VDE) model of heat capacity developed in this work better enables the informed design of next-generation devices.
KW - Materials Design
KW - Heat Capacity
KW - Machine learning potentials
KW - Thermal Management
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-645711
DO - https://doi.org/10.1016/j.joule.2025.102054
SN - 2542-4351
VL - 9
IS - 8
SP - 1
EP - 12
PB - Elsevier Inc.
AN - OPUS4-64571
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Miliūtė, Aistė
A1 - Bustamante, Joana
A1 - Mieller, Björn
A1 - Stawski, Tomasz
A1 - George, Janine
A1 - Knoop, F.
T1 - High-quality zirconium vanadate samples for negative thermal expansion (NTE) analysis
N2 - Zirconium vanadate (ZrV2O7) is a well-known negative thermal expansion (NTE) material which exhibits significant isotropic contraction over a broad temperature range (~150°C < T < 800°C). The linear thermal expansion coefficient of ZrV2O7 is −7.1×10-6 K-1. Therefore, it can be used to create composites with controllable expansion coefficients and prevent destruction by thermal shock.
Material characterization, leading to application, requires pure, homogenous samples of high crystallinity via a reliable synthesis route. While there is a selection of described syntheses in the literature, it still needs to be addressed which synthesis route leads to truly pure and homogenous samples. Here, we study the influence of the synthesis methods (solid-state, sol-gel, solvothermal) and their parameters on the sample's purity, crystallinity, and homogeneity. The reproducibility of results and data obtained with scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry, and thermogravimetric analysis (DSC/TGA) were analyzed extensively. The sol-gel method proves superior to the solid-state method and produces higher-quality samples over varying parameters. Sample purity also plays an important role in NTE micro and macro-scale characterizations that explain the impact of porosity versus structural changes.
Moreover, we implement ab-initio-based vibrational computations with partially treated anharmonicity (quasi-harmonic approximation, temperature-dependent effective harmonic potentials) in combination with experimental methods to follow and rationalize the negative thermal expansion in this material, including the influence of the local structure disorder, microstructure, and defects. Khosrovani et al. and Korthuis et al., in a series of diffraction experiments, attributed the thermal contraction of ZrV2O7 to the transverse thermal motion of oxygen atoms in V-O-V linkages. In addition to previous explanations, we hypothesize that local disorder develops in ZrV2O7 crystals during heating.
We are working on the experimental ZrV2O7 development and discuss difficulties one might face in the process as well as high-quality sample significance in further investigation. The obtained samples are currently used in the ongoing research of structure analysis and the negative thermal expansion mechanism.
T2 - TDEP2023: Finite-temperature and anharmonic response properties of solids in theory and practice
CY - Linköping, Sweden
DA - 21.08.2023
KW - NTE
KW - Sol-gel
KW - Solid-state
KW - Ab-initio
KW - TDEP
PY - 2023
AN - OPUS4-58135
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Miliūtė, Aistė
A1 - Bustamante, Joana
A1 - Mieller, Björn
A1 - Stawski, Tomasz
A1 - George, Janine
A1 - Knoop, F.
T1 - High-quality zirconium vanadate samples for negative thermal expansion (NTE) analysis
N2 - Zirconium vanadate (ZrV2O7) is a well-known negative thermal expansion (NTE) material which exhibits significant isotropic contraction over a broad temperature range (~150°C < T < 800°C). The linear thermal expansion coefficient of ZrV2O7 is −7.1×10-6 K-. Therefore, it can be used to create composites with controllable expansion coefficients and prevent destruction by thermal shock.
Material characterization, leading to application, requires pure, homogenous samples of high crystallinity via a reliable synthesis route. While there is a selection of described syntheses in the literature, it still needs to be addressed which synthesis route leads to truly pure and homogenous samples. Here, we study the influence of the synthesis methods (solid-state, sol-gel, solvothermal) and their parameters on the sample's purity, crystallinity, and homogeneity. The reproducibility of results and data obtained with scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry, and thermogravimetric analysis (DSC/TGA) were analyzed extensively. The sol-gel method proves superior to the solid-state method and produces higher-quality samples over varying parameters. Sample purity also plays an important role in NTE micro and macro-scale characterizations that explain the impact of porosity versus structural changes.
Moreover, we implement ab-initio-based vibrational computations with partially treated anharmonicity (quasi-harmonic approximation, temperature-dependent effective harmonic potentials) in combination with experimental methods to follow and rationalize the negative thermal expansion in this material, including the influence of the local structure disorder, microstructure, and defects. Khosrovani et al. and Korthuis et al., in a series of diffraction experiments, attributed the thermal contraction of ZrV2O7 to the transverse thermal motion of oxygen atoms in V-O-V linkages. In addition to previous explanations, we hypothesize that local disorder develops in ZrV2O7 crystals during heating.
We are working on the experimental ZrV2O7 development and discuss difficulties one might face in the process as well as high-quality sample significance in further investigation. The obtained samples are currently used in the ongoing research of structure analysis and the negative thermal expansion mechanism.
T2 - 4th International Symposium on Negative Thermal Expansion and Related Materials (ISNTE-4)
CY - Padua, Italy
DA - 04.07.2023
KW - NTE
KW - Sol-gel
KW - Solid-state
KW - Ab-initio
KW - TDEP
PY - 2023
AN - OPUS4-58132
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Miliūtė, Aistė
A1 - Bustamante, Joana
A1 - Mieller, Björn
A1 - Stawski, Tomasz
A1 - George, Janine
A1 - Knoop, F.
T1 - High-quality zirconium vanadate samples for negative thermal expansion (NTE) analysis
N2 - Zirconium vanadate (ZrV2O7) is a well-known negative thermal expansion (NTE) material which exhibits significant isotropic contraction over a broad temperature range (~150°C < T < 800°C). The linear thermal expansion coefficient of ZrV2O7 is −7.1×10-6 K-. Therefore, it can be used to create composites with controllable expansion coefficients and prevent destruction by thermal shock.
Material characterization, leading to application, requires pure, homogenous samples of high crystallinity via a reliable synthesis route. While there is a selection of described syntheses in the literature, it still needs to be addressed which synthesis route leads to truly pure and homogenous samples. Here, we study the influence of the synthesis methods (solid-state, sol-gel, solvothermal) and their parameters on the sample's purity, crystallinity, and homogeneity. The reproducibility of results and data obtained with scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry, and thermogravimetric analysis (DSC/TGA) were analyzed extensively. The sol-gel method proves superior to the solid-state method and produces higher-quality samples over varying parameters. Sample purity also plays an important role in NTE micro and macro-scale characterizations that explain the impact of porosity versus structural changes.
Moreover, we implement ab-initio-based vibrational computations with partially treated anharmonicity (quasi-harmonic approximation, temperature-dependent effective harmonic potentials) in combination with experimental methods to follow and rationalize the negative thermal expansion in this material, including the influence of the local structure disorder, microstructure, and defects. Khosrovani et al. and Korthuis et al., in a series of diffraction experiments, attributed the thermal contraction of ZrV2O7 to the transverse thermal motion of oxygen atoms in V-O-V linkages. In addition to previous explanations, we hypothesize that local disorder develops in ZrV2O7 crystals during heating.
We are working on the experimental ZrV2O7 development and discuss difficulties one might face in the process as well as high-quality sample significance in further investigation. The obtained samples are currently used in the ongoing research of structure analysis and the negative thermal expansion mechanism.
T2 - 16th International conference on materials chemistry (MC16)
CY - Dublin, Ireland
DA - 03.07.2023
KW - NTE
KW - Sol-gel
KW - Solid-state
KW - Ab-initio
KW - TDEP
PY - 2023
AN - OPUS4-58134
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Ganose, Alex M.
A1 - Sahasrabuddhe, Hrushikesh
A1 - Asta, Mark
A1 - Beck, Kevin
A1 - Biswas, Tathagata
A1 - Bonkowski, Alexander
A1 - Bustamante, Joana
A1 - Chen, Xin
A1 - Chiang, Yuan
A1 - Chrzan, Daryl C.
A1 - Clary, Jacob
A1 - Cohen, Orion A.
A1 - Ertural, Christina
A1 - Gallant, Max C.
A1 - George, Janine
A1 - Gerits, Sophie
A1 - Goodall, Rhys E. A.
A1 - Guha, Rishabh D.
A1 - Hautier, Geoffroy
A1 - Horton, Matthew
A1 - Inizan, T. J.
A1 - Kaplan, Aaron D.
A1 - Kingsbury, Ryan S.
A1 - Kuner, Matthew C.
A1 - Li, Bryant
A1 - Linn, Xavier
A1 - McDermott, Matthew J.
A1 - Mohanakrishnan, Rohith Srinivaas
A1 - Naik, Aakash A.
A1 - Neaton, Jeffrey B.
A1 - Parmar, Shehan M.
A1 - Persson, Kristin A.
A1 - Petretto, Guido
A1 - Purcell, Thomas A. R.
A1 - Ricci, Francesco
A1 - Rich, Benjamin
A1 - Riebesell, Janosh
A1 - Rignanese, Gian-Marco
A1 - Rosen, Andrew S.
A1 - Scheffler, Matthias
A1 - Schmidt, Jonathan
A1 - Shen, Jimmy-Xuan
A1 - Sobolev, Andrei
A1 - Sundararaman, Ravishankar
A1 - Tezak, Cooper
A1 - Trinquet, Victor
A1 - Varley, Joel B.
A1 - Vigil-Fowler, Derek
A1 - Wang, Duo
A1 - Waroquiers, David
A1 - Wen, Mingjian
A1 - Yang, Han
A1 - Zheng, Hui
A1 - Zheng, Jiongzhi
A1 - Zhu, Zhuoying
A1 - Jain, Anubhav
T1 - Correction: Atomate2: Modular workflows for materials science
N2 - Correction for “Atomate2: modular workflows for materials science” by Alex M. Ganose et al., Digital Discovery, 2025, 4, 1944–1973, https://doi.org/10.1039/D5DD00019J.
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-640297
DO - https://doi.org/10.1039/d5dd90036k
SN - 2635-098X
SP - 1
EP - 2
PB - Royal Society of Chemistry (RSC)
CY - Cambridge
AN - OPUS4-64029
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Miliūtė, Aistė
A1 - Bustamante, Joana
A1 - Karafiludis, Stephanos
A1 - Zöllner, Moritz
A1 - Eddah, Mustapha
A1 - Emmerling, Franziska
A1 - Mieller, Björn
A1 - George, Janine
A1 - Stawski, Tomasz M.
T1 - Synthesis and phase purity of the negative thermal expansion material ZrV2O7
N2 - Synthesis of pure, homogeneous, and reproducible materials is key for the comprehensive understanding, design, and tailoring of material properties. In this study, we focus on the synthesis of ZrV2O7, a material known for its negative thermal expansion properties. We investigate the influence of solid-state and wet chemistry synthesis methods on the purity and homogeneity of ZrV2O7 samples. Our findings indicate that different synthesis methods significantly impact the material's characteristics. The solid-state reaction provided high-purity material through extended milling time and repeated calcination cycles, while the sol-gel reaction enabled a “near-atomic” level of mixing and, therefore, homogenous phase-pure ZrV2O7. We confirmed purity via X-ray diffraction and Raman spectroscopy, highlighting differences between phase-pure and multiphase ceramics. These analytical techniques allowed us to distinguish subtle differences in the structure of the material. Based on ab initio simulated phonon data, we were able to interpret the Raman spectra and visualise Raman active atom vibrations. We show that phase purity enables the unbiased characterisation of material properties such as negative thermal expansion.
KW - NTE
KW - Sol-gel
KW - Solid-state
KW - Ab-initio
KW - XRD
KW - Raman
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624013
DO - https://doi.org/10.1039/d4tc04095c
SN - 2050-7534
SP - 1
EP - 13
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-62401
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -