EPR spectroscopy reveals the universality class and dynamic effects of the [NH4][Zn(HCOO)3] hybrid formate framework.
}}, author = {{Navickas, Marius and Giriūnas, Laisvydas and Kalendra, Vidmantas and Biktagirov, Timur and Gerstmann, Uwe and Schmidt, Wolf Gero and Mączka, Mirosław and Pöppl, Andreas and Banys, Jūras and Šimėnas, Mantas}}, issn = {{1463-9076}}, journal = {{Physical Chemistry Chemical Physics}}, pages = {{8513--8521}}, title = {{{Electron paramagnetic resonance study of ferroelectric phase transition and dynamic effects in a Mn2+ doped [NH4][Zn(HCOO)3] hybrid formate framework}}}, doi = {{10.1039/d0cp01612h}}, volume = {{22}}, year = {{2020}}, } @article{29745, author = {{Biktagirov, Timur and Gerstmann, Uwe}}, issn = {{2643-1564}}, journal = {{Physical Review Research}}, keywords = {{General Engineering}}, number = {{2}}, publisher = {{American Physical Society (APS)}}, title = {{{Spin-orbit driven electrical manipulation of the zero-field splitting in high-spin centers in solids}}}, doi = {{10.1103/physrevresearch.2.023071}}, volume = {{2}}, year = {{2020}}, } @article{19189, abstract = {{Density-functional theory calculations of (TiO2)n clusters (n = 1–5) in the gas phase and adsorbed on pristine graphene as well as graphene quantum dots are presented. The cluster adsorption is found to be dominated by van der Waals forces. The electronic structure and in particular the excitation energies of the bare clusters and the TiO2/graphene composites are found to vary largely in dependence on the size of the respective constituents. This holds in particular for the energy and the spatial localization of the highest occupied and lowest unoccupied molecular orbitals. In addition to a substantial gap narrowing, a pronounced separation of photoexcited electrons and holes is predicted in some instances. This is expected to prolong the lifetime of photoexcited carriers. Altogether, TiO2/graphene composites are predicted to be promising photocatalysts with improved electronic and photocatalytic properties compared to bulk TiO2.}}, author = {{Badalov, Sabuhi and Wilhelm, René and Schmidt, Wolf Gero}}, issn = {{0192-8651}}, journal = {{Journal of Computational Chemistry}}, pages = {{1921--1930}}, publisher = {{Willey}}, title = {{{Photocatalytic properties of graphene‐supported titania clusters from density‐functional theory}}}, doi = {{10.1002/jcc.26363}}, year = {{2020}}, } @article{20682, author = {{Bocchini, Adriana and Eigner, Christof and Silberhorn, Christine and Schmidt, Wolf Gero and Gerstmann, Uwe}}, journal = {{Phys. Rev. Materials}}, pages = {{124402}}, publisher = {{American Physical Society}}, title = {{{Understanding gray track formation in KTP: Ti^3+ centers studied from first principles}}}, doi = {{10.1103/PhysRevMaterials.4.124402}}, volume = {{4}}, year = {{2020}}, } @article{29744, abstract = {{A hole transfer from an excited Ru unit towards graphene oxide significantly improved the photocatalytic activity of the complexes.
}}, author = {{Rosenthal, Marta and Lindner, Jörg and Gerstmann, Uwe and Meier, Armin and Schmidt, Wolf Gero and Wilhelm, René}}, issn = {{2046-2069}}, journal = {{RSC Advances}}, keywords = {{General Chemical Engineering, General Chemistry}}, number = {{70}}, pages = {{42930--42937}}, publisher = {{Royal Society of Chemistry (RSC)}}, title = {{{A photoredox catalysed Heck reaction via hole transfer from a Ru(ii)-bis(terpyridine) complex to graphene oxide}}}, doi = {{10.1039/d0ra08749a}}, volume = {{10}}, year = {{2020}}, } @article{17068, author = {{Braun, Christian and Neufeld, Sergej and Gerstmann, Uwe and Sanna, S. and Plaickner, J. and Speiser, E. and Esser, N. and Schmidt, Wolf Gero}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, number = {{14}}, title = {{{Vibration-Driven Self-Doping of Dangling-Bond Wires on Si(553)-Au Surfaces}}}, doi = {{10.1103/physrevlett.124.146802}}, volume = {{124}}, year = {{2020}}, } @article{10014, abstract = {{The cubic, tetragonal, and orthorhombic phase of potassium niobate (KNbO3) are studied based on density-functional theory. Starting from the relaxed atomic geometries, we analyze the influence of self-energy corrections on the electronic band structure within the GW approximation. We find that quasiparticle shifts widen the direct (indirect) band gap by 1.21 (1.44), 1.58 (1.55), and 1.67 (1.64) eV for the cubic, tetragonal, and orthorhombic phase, respectively. By solving the Bethe-Salpeter equation, we obtain the linear dielectric function with excitonic and local-field effects, which turn out to be essential for good agreement with experimental data. From our results, we extract an exciton binding energy of 0.6, 0.5, and 0.5 eV for the cubic, tetragonal, and orthorhombic phase, respectively. Furthermore, we investigate the nonlinear second-harmonic generation (SHG) both theoretically and experimentally. The frequency-dependent second-order polarization tensor of orthorhombic KNbO3 is measured for incoming photon energies between 1.2 and 1.6 eV. In addition, calculations within the independent-(quasi)particle approximation are performed for the tetragonal and orthorhombic phase. The novel experimental data are in excellent agreement with the quasiparticle calculations and resolve persistent discrepancies between earlier experimental measurements and ab initio results reported in the literature.}}, author = {{Schmidt, Falko and Riefer, Arthur and Schmidt, Wolf Gero and Schindlmayr, Arno and Imlau, Mirco and Dobener, Florian and Mengel, Nils and Chatterjee, Sangam and Sanna, Simone}}, issn = {{2475-9953}}, journal = {{Physical Review Materials}}, number = {{5}}, publisher = {{American Physical Society}}, title = {{{Quasiparticle and excitonic effects in the optical response of KNbO3}}}, doi = {{10.1103/PhysRevMaterials.3.054401}}, volume = {{3}}, year = {{2019}}, } @article{29746, author = {{Nicholson, C. W. and Puppin, M. and Lücke, A. and Gerstmann, Uwe and Krenz, Marvin and Schmidt, Wolf Gero and Rettig, L. and Ernstorfer, R. and Wolf, M.}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{15}}, publisher = {{American Physical Society (APS)}}, title = {{{Excited-state band mapping and momentum-resolved ultrafast population dynamics in In/Si(111) nanowires investigated with XUV-based time- and angle-resolved photoemission spectroscopy}}}, doi = {{10.1103/physrevb.99.155107}}, volume = {{99}}, year = {{2019}}, } @article{10015, author = {{Dues, Christof and Schmidt, Wolf Gero and Sanna, Simone}}, issn = {{2470-1343}}, journal = {{ACS Omega}}, pages = {{3850--3859}}, title = {{{Water Splitting Reaction at Polar Lithium Niobate Surfaces}}}, doi = {{10.1021/acsomega.8b03271}}, year = {{2019}}, } @article{13365, abstract = {{The KTiOPO4 (KTP) band structure and dielectric function are calculated on various levels of theory starting from density-functional calculations. Within the independent-particle approximation an electronic transport gap of 2.97 eV is obtained that widens to about 5.23 eV when quasiparticle effects are included using the GW approximation. The optical response is shown to be strongly anisotropic due to (i) the slight asymmetry of the TiO6 octahedra in the (001) plane and (ii) their anisotropic distribution along the [001] and [100] directions. In addition, excitonic effects are very important: The solution of the Bethe–Salpeter equation indicates exciton binding energies of the order of 1.5 eV. Calculations that include both quasiparticle and excitonic effects are in good agreement with the measured reflectivity.}}, author = {{Neufeld, Sergej and Bocchini, Adriana and Gerstmann, Uwe and Schindlmayr, Arno and Schmidt, Wolf Gero}}, issn = {{2515-7639}}, journal = {{Journal of Physics: Materials}}, pages = {{045003}}, publisher = {{IOP Publishing}}, title = {{{Potassium titanyl phosphate (KTP) quasiparticle energies and optical response}}}, doi = {{10.1088/2515-7639/ab29ba}}, volume = {{2}}, year = {{2019}}, } @article{13429, author = {{Bocchini, Adriana and Neufeld, Sergej and Gerstmann, Uwe and Schmidt, Wolf Gero}}, issn = {{0953-8984}}, journal = {{Journal of Physics: Condensed Matter}}, pages = {{385401}}, title = {{{Oxygen and potassium vacancies in KTP calculated from first principles}}}, doi = {{10.1088/1361-648x/ab295c}}, volume = {{31}}, year = {{2019}}, } @article{10018, author = {{Schmidt, Claudia and Bühler, J. and Heinrich, A.-C. and Allerbeck, J. and Podzimski, R. and Berghoff, Daniel and Meier, Torsten and Schmidt, Wolf Gero and Reichl, C. and Wegscheider, W. and Brida, D. and Leitenstorfer, A.}}, issn = {{2041-1723}}, journal = {{Nature Communications}}, title = {{{Signatures of transient Wannier-Stark localization in bulk gallium arsenide}}}, doi = {{10.1038/s41467-018-05229-x}}, volume = {{9}}, 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{13406, author = {{Mamiyev, Z. and Lichtenstein, T. and Tegenkamp, C. and Braun, Christian and Schmidt, Wolf Gero and Sanna, S. and Pfnür, H.}}, issn = {{2475-9953}}, journal = {{Physical Review Materials}}, number = {{6}}, title = {{{Plasmon spectroscopy: Robust metallicity of Au wires on Si(557) upon oxidation}}}, doi = {{10.1103/physrevmaterials.2.066002}}, volume = {{2}}, year = {{2018}}, } @article{13403, author = {{Biktagirov, Timur and Schmidt, Wolf Gero and Gerstmann, Uwe and Yavkin, Boris and Orlinskii, Sergei and Baranov, Pavel and Dyakonov, Vladimir and Soltamov, Victor}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{19}}, title = {{{Polytypism driven zero-field splitting of silicon vacancies in 6H-SiC}}}, doi = {{10.1103/physrevb.98.195204}}, volume = {{98}}, year = {{2018}}, }