@phdthesis{16327, author = {{Müller, Patrick}}, title = {{{ Experimental and theoretical (high energy resolution) X-ray absorption and emission spectroscopy / vorgelegt von Patrick Müller ; [Promotionskommission: Prof. Dr.-Ing. Hans-Joachim Warnecke, Vorsitz; Prof. Dr. Matthias Bauer, Erstgutachter; Prof. Dr. Thomas D. Kühne, Zweitgutachter; Prof. Dr. Wolf Gero Schmidt]}}}, doi = {{10.17619/UNIPB/1-705}}, year = {{2019}}, } @article{13211, author = {{Kodalle, Tim and Kormath Madam Raghupathy, Ramya and Bertram, Tobias and Maticiuc, Natalia and Yetkin, Hasan A and Gunder, René and Schlatmann, Rutger and Kühne, Thomas D and Kaufmann, Christian A and Mirhosseini, Hossein}}, journal = {{physica status solidi (RRL)--Rapid Research Letters}}, number = {{3}}, pages = {{1800564}}, publisher = {{John Wiley & Sons, Ltd}}, title = {{{Properties of Co-Evaporated RbInSe2 Thin Films}}}, doi = {{10.1002/pssr.201800564}}, volume = {{13}}, year = {{2019}}, } @article{13225, abstract = {{Abstract The effect of extending the O−H bond length(s) in water on the hydrogen-bonding strength has been investigated using static ab initio molecular orbital calculations. The “polar flattening” effect that causes a slight σ-hole to form on hydrogen atoms is strengthened when the bond is stretched, so that the σ-hole becomes more positive and hydrogen bonding stronger. In opposition to this electronic effect, path-integral ab initio molecular-dynamics simulations show that the nuclear quantum effect weakens the hydrogen bond in the water dimer. Thus, static electronic effects strengthen the hydrogen bond in H2O relative to D2O, whereas nuclear quantum effects weaken it. These quantum fluctuations are stronger for the water dimer than in bulk water.}}, author = {{Clark, Timothy and Heske, Julian Joachim and Kühne, Thomas}}, journal = {{ChemPhysChem}}, keywords = {{ab initio calculations, bond theory, hydrogen bonds, isotope effects, solvent effects}}, pages = {{1--6}}, title = {{{Opposing Electronic and Nuclear Quantum Effects on Hydrogen Bonds in H2O and D2O}}}, doi = {{10.1002/cphc.201900839}}, volume = {{20}}, year = {{2019}}, } @article{13232, author = {{Kaliannan, Naveen Kumar and Henao Aristizabal, Andres and Wiebeler, Hendrik and Zysk, Frederik and Ohto, Tatsuhiko and Nagata, Yuki and D. Kühne, Thomas}}, journal = {{Molecular Physics}}, pages = {{1--10}}, publisher = {{Taylor & Francis}}, title = {{{Impact of intermolecular vibrational coupling effects on the sum-frequency generation spectra of the water/air interface}}}, doi = {{10.1080/00268976.2019.1620358}}, year = {{2019}}, } @article{13233, author = {{Müller, Patrick and Neuba, Adam and Flörke, Ulrich and Henkel, Gerald and Kühne, Thomas D. and Bauer, Matthias}}, journal = {{The Journal of Physical Chemistry A}}, number = {{16}}, pages = {{3575--3581}}, title = {{{Experimental and Theoretical High Energy Resolution Hard X-ray Absorption and Emission Spectroscopy on Biomimetic Cu2S2 Complexes}}}, doi = {{10.1021/acs.jpca.9b00463}}, volume = {{123}}, year = {{2019}}, } @article{13236, abstract = {{Thermal treatment of hexaazatriphenylene-hexacarbonitrile (HAT-CN) in the temperature range from 500 °C to 700 °C leads to precise control over the degree of condensation{,} and thus atomic construction and porosity of the resulting C2N-type materials. Depending on the condensation temperature of HAT-CN{,} nitrogen contents of more than 30 at% can be reached. In general{,} these carbons show adsorption properties which are comparable to those known for zeolites but their pore size can be adjusted over a wider range. At condensation temperatures of 525 °C and below{,} the uptake of nitrogen gas remains negligible due to size exclusion{,} but the internal pores are large and polarizing enough that CO2 can still adsorb on part of the internal surface. This leads to surprisingly high CO2 adsorption capacities and isosteric heat of adsorption of up to 52 kJ mol−1. Theoretical calculations show that this high binding enthalpy arises from collective stabilization effects from the nitrogen atoms in the C2N layers surrounding the carbon atom in the CO2 molecule and from the electron acceptor properties of the carbon atoms from C2N which are in close proximity to the oxygen atoms in CO2. A true CO2 molecular sieving effect is achieved for the first time in such a metal-free organic material with zeolite-like properties{,} showing an IAST CO2/N2 selectivity of up to 121 at 298 K and a N2/CO2 ratio of 90/10 without notable changes in the CO2 adsorption properities over 80 cycles.}}, author = {{Walczak, Ralf and Savateev, Aleksandr and Heske, Julian Joachim and Tarakina, Nadezda V. and Sahoo, Sudhir and Epping, Jan D. and Kühne, Thomas and Kurpil, Bogdan and Antonietti, Markus and Oschatz, Martin}}, journal = {{Sustainable Energy Fuels}}, pages = {{--}}, publisher = {{The Royal Society of Chemistry}}, title = {{{Controlling the strength of interaction between carbon dioxide and nitrogen-rich carbon materials by molecular design}}}, doi = {{10.1039/C9SE00486F}}, year = {{2019}}, } @article{13237, author = {{Elgabarty, Hossam and Kaliannan, Naveen Kumar and Kühne, Thomas D.}}, journal = {{Scientific Reports}}, pages = {{10002}}, title = {{{Enhancement of the asymmetry in the hydrogen bond network of liquid water by an ultrafast electric field pulse}}}, doi = {{10.1038/s41598-019-46449-5}}, volume = {{ 9}}, year = {{2019}}, } @article{13230, abstract = {{The behavior of alkali atom point defects in polycrystalline CuInSe2 is studied. In this work, three grain boundary models, one coherent twin boundary and two twin boundaries with dislocation cores, are considered. Total energy calculations show that all alkali metals tend to segregate at the grain boundaries. In addition, the segregation of alkali atoms is more pronounced at the grain boundaries with the dislocation cores. The diffusion of alkali metals along and near grain boundaries is studied as well. The results show that the diffusion of alkali atoms in the grain boundary models is faster than within the bulk. In addition, the ion exchange between Na and Rb atoms at the grain boundaries leads to the Rb enrichment at the grain boundaries and the increase of the Na concentration in the bulk. While the effects of Na and Rb point defects on the electronic structure of the grain boundary with the anion-core dislocation are similar, Rb atoms passivate the grain boundary with the cation-core dislocation more effectively than Na. This can explain the further improvement of the solar cell performance after the RbF-postdeposition treatment.}}, author = {{ Chugh, Manjusha and Kühne, Thomas D. and Mirhosseini, Hossein}}, journal = {{ACS Applied Materials & Interfaces}}, number = {{16}}, pages = {{14821−14829}}, publisher = {{American Chemical Society}}, title = {{{Diffusion of Alkali Metals in Polycrystalline CuInSe2 and Their Role in the Passivation of Grain Boundaries}}}, doi = {{10.1021/acsami.9b02158}}, volume = {{11}}, year = {{2019}}, } @article{44992, author = {{Brehm, Martin and Thomas, M.}}, journal = {{J. Chem. Theory Comput.}}, pages = {{3901--3905}}, title = {{{Computing Bulk Phase Resonance Raman Spectra from ab initio Molecular Dynamics and Real-Time TDDFT}}}, doi = {{10.1021/acs.jctc.9b00512}}, volume = {{15 (7)}}, year = {{2019}}, } @article{44991, author = {{Brehm, Martin and Pulst, M. and Kressler, J. and Sebastiani, D.}}, journal = {{J. Phys. Chem. B}}, pages = {{3994--4003}}, title = {{{Triazolium-Based Ionic Liquids – A Novel Class of Cellulose Solvents}}}, doi = {{10.1021/acs.jpcb.8b12082}}, volume = {{123 (18)}}, year = {{2019}}, } @article{21, abstract = {{We address the general mathematical problem of computing the inverse p-th root of a given matrix in an efficient way. A new method to construct iteration functions that allow calculating arbitrary p-th roots and their inverses of symmetric positive definite matrices is presented. We show that the order of convergence is at least quadratic and that adaptively adjusting a parameter q always leads to an even faster convergence. In this way, a better performance than with previously known iteration schemes is achieved. The efficiency of the iterative functions is demonstrated for various matrices with different densities, condition numbers and spectral radii.}}, author = {{Richters, Dorothee and Lass, Michael and Walther, Andrea and Plessl, Christian and Kühne, Thomas}}, journal = {{Communications in Computational Physics}}, number = {{2}}, pages = {{564--585}}, publisher = {{Global Science Press}}, title = {{{A General Algorithm to Calculate the Inverse Principal p-th Root of Symmetric Positive Definite Matrices}}}, doi = {{10.4208/cicp.OA-2018-0053}}, volume = {{25}}, year = {{2019}}, } @article{15739, author = {{Azadi, Sam and Kühne, Thomas D.}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{15}}, pages = {{155103--155109}}, title = {{{Unconventional phase III of high-pressure solid hydrogen}}}, doi = {{10.1103/physrevb.100.155103}}, volume = {{100}}, year = {{2019}}, } @article{20, abstract = {{Approximate computing has shown to provide new ways to improve performance and power consumption of error-resilient applications. While many of these applications can be found in image processing, data classification or machine learning, we demonstrate its suitability to a problem from scientific computing. Utilizing the self-correcting behavior of iterative algorithms, we show that approximate computing can be applied to the calculation of inverse matrix p-th roots which are required in many applications in scientific computing. Results show great opportunities to reduce the computational effort and bandwidth required for the execution of the discussed algorithm, especially when targeting special accelerator hardware.}}, author = {{Lass, Michael and Kühne, Thomas and Plessl, Christian}}, issn = {{1943-0671}}, journal = {{Embedded Systems Letters}}, number = {{2}}, pages = {{ 33--36}}, publisher = {{IEEE}}, title = {{{Using Approximate Computing for the Calculation of Inverse Matrix p-th Roots}}}, doi = {{10.1109/LES.2017.2760923}}, volume = {{10}}, year = {{2018}}, } @article{13209, abstract = {{We performed ab initio calculations to study oxygen and hydrogen point defects in the CuInSe2 (CISe) solar-cell material. We found that H interstitial defects (when one H atom is surrounded by four Se atoms) and HCu (when a H atom is replacing a Cu atom) are the most stable defects. Whereas these H substitutional defects remain neutral, H interstitial defects act as donor defects and are detrimental to the cell performance. The incorporation of H2 into the CISe lattice, on the other hand, is harmless to the p-type conductivity. Oxygen atoms tend to either substitute Se atoms in the CISe lattice or form interstitial defects, though the formation of substitutional defects is more favorable. All oxygen point defects have high formation energies, which results in a low concentration of these defects in CISe. However, the presence of oxygen in the system leads to the formation of secondary phases such as In2O3 and InCuO2. In addition to the point defects, we studied the adsorption of H2O molecules on a defect-free surface and a surface with a (2VCu + InCu) defect using the ab initio thermodynamics technique. Our results indicate that the dissociative water adsorption on the CISe surface is energetically unfavorable. Furthermore, in order to obtain a water-free surface, the surface with defects has to be calcined at a higher temperature compared to the defect-free surface.}}, author = {{Sahoo, Sudhir and Kormath Madam Raghupathy, Ramya and Kühne, Thomas and Mirhosseini, Hossein}}, journal = {{J. Phys. Chem. C}}, number = {{37}}, pages = {{21202--21209}}, title = {{{Theoretical Investigation of Interaction of CuInSe2 Absorber Material with Oxygen, Hydrogen, and Water}}}, doi = {{10.1021/acs.jpcc.8b06709}}, volume = {{122}}, year = {{2018}}, } @article{13210, abstract = {{In this work, we investigated ternary chalcogenide semiconductors to identify promising p-type transparent conducting materials (TCMs). High-throughput calculations were employed to find the compounds that satisfies our screening criteria. Our screening strategy was based on the size of band gaps, the values of hole effective masses, and p-type dopability. Our search led to the identification of seven promising compounds (IrSbS, Ba2GeSe4, Ba2SiSe4, Ba(BSe3)2, VCu3S4, NbCu3Se4, and CuBS2) as potential TCM candidates. In addition, branch point energy and optical absorption spectra calculations support our findings. Our results open a new direction for the design and development of p-type TCMs.}}, author = {{Kormath Madam Raghupathy, Ramya and Wiebeler, Hendrik and Kühne, Thomas and Felser, Claudia and Mirhosseini, Hossein}}, journal = {{Chemistry of Materials}}, number = {{19}}, pages = {{6794--6800}}, publisher = {{American Chemical Society}}, title = {{{Database screening of ternary chalcogenides for p-type transparent conductors}}}, doi = {{10.1021/acs.chemmater.8b02719}}, volume = {{30}}, year = {{2018}}, } @article{13405, author = {{Müller, Patrick and Karhan, Kristof and Krack, Matthias and Gerstmann, Uwe and Schmidt, Wolf Gero and Bauer, Matthias and Kühne, Thomas D.}}, issn = {{0192-8651}}, journal = {{Journal of Computational Chemistry}}, pages = {{712--716}}, title = {{{Impact of finite-temperature and condensed-phase effects on theoretical X-ray absorption spectra of transition metal complexes}}}, doi = {{10.1002/jcc.25641}}, year = {{2018}}, } @article{44989, author = {{Cerajewski, U. and Träger, J. and Henkel, S. and Roos, A. H. and Brehm, Martin and Hinderberger, D.}}, journal = {{Phys. Chem. Chem. Phys.}}, pages = {{29591--29600}}, title = {{{Nanoscopic Structures and Molecular Interactions Leading to a Dystectic and two Eutectic Points in [EMIm][Cl] / Urea Mixtures}}}, doi = {{10.1039/C8CP04912B}}, volume = {{20}}, year = {{2018}}, } @article{44986, author = {{Gehrke, S. and von Domaros, M. and Clark, R. and Hollóczki, O. and Brehm, Martin and Welton, T. and Luzar, A. and Kirchner, B.}}, journal = {{Faraday Discuss.}}, pages = {{219--245}}, title = {{{Structure and Lifetimes in Ionic Liquids and their Mixtures}}}, doi = {{10.1039/C7FD00166E}}, volume = {{206}}, year = {{2018}}, } @article{44988, author = {{Pylaeva, S. and Brehm, Martin and Sebastiani, D.}}, journal = {{Sci. Rep.}}, pages = {{13626}}, title = {{{Salt Bridge in Aqueous Solution: Strong Structural Motifs but Weak Enthalpic Effects}}}, doi = {{10.1038/s41598-018-31935-z}}, volume = {{8}}, year = {{2018}}, } @article{44990, author = {{Brehm, Martin and Thomas, M.}}, journal = {{J. Chem. Inf. Model.}}, pages = {{2092--2107}}, title = {{{An Efficient Lossless Compression Algorithm for Trajectories of Atom Positions and Volumetric Data}}}, doi = {{10.1021/acs.jcim.8b00501}}, volume = {{58 (10)}}, year = {{2018}}, }