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Incommensurate crystal structures do not display three-dimensional periodicity. Discovered in the 1960's, a mathematical model has been established in 1974 only. Incommensurate structures belong to the big family of aperiodic structures. The modulation of ...
We performed fully first principles quantum mechanical calculations of the ground and excited state geometries and harmonic vibrational frequencies of two prototype cationic Ir(III) complexes showing high emission quantum efficiencies. Thanks to recent the ...
Protonation of norbom-5-en-2-one gives 6-oxo-2-norbomyl cation (2) as most stable C7H9O+ cation. Quantum calculations at B3LYP/6-31G(d) level (gas phase, 1 atm, 25 degrees C) predict a C-s-structure for 2 that can be represented as an intramolecular pi-com ...
Using hybrid density functionals, we investigate the origin of the large band gap experimentally observed at the 6H-SiC(0001) surface when passivated by an epitaxial silicon oxynitride layer. In order to distinguish the effects resulting from the interfaci ...
The magnetic properties of disordered graphene and irradiated graphite are systematically studied using a combination of mean-field Hubbard model and first-principles calculations. By considering large-scale disordered models of graphene, I conclude that o ...
Band offsets at semiconductor-oxide interfaces are determined through a scheme based on hybrid density functionals, which incorporate a fraction alpha of Hartree-Fock exchange. For each bulk component, the fraction alpha is tuned to reproduce the experimen ...
The determination of band alignments and defect levels is demonstrated for the technologically relevant Si-SiO2-HfO2 gate stack. The proposed scheme, which combines first-principles molecular dynamics for model generation and hybrid density functionals for ...
We present a detailed analysis of the addition-elimination reaction pathways for the gas-phase conversion of molecular hydrogen and methane on FeO(+) to water and methanol, respectively, using first-principles calculations. These two reactions represent pa ...
Insight into the conformations and aggregation of alginic acid was gained by measuring its diffusion coefficient at very dilute concentrations using fluorescence correlation spectroscopy. Both the pH and ionic strength (I) had an important influence on the ...
We investigate the DFT + U approach as a viable solution to describe the low-lying states of ligated and unligated iron heme complexes. Besides their central role in organometallic chemistry, these compounds represent a paradigmatic case where LDA, GGA, an ...