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The reactions of (super 1)S and (super 3)D Cu(super +) ions with N2O are studied using the help of ab initio methods. The calculations showed that bare (super 1)S Cu(super +) ions are relatively inert with respect to N2O.

The reaction of 3d transition metal atoms with N2O is studied to examine charge transfer process in the reaction mechanism by combination of density functional theory and the coupled cluster method CCSD(T). Results showed no charge transfer from the transition metal toward N2O for Sc, Ti and V transition state, whereas charge transfer between the metal 4s orbital and the in-plane N2O LUMO is an important process, when moving from Cr to Cu in the 3d transition series.

Research was conducted to examine the structure of the local Co(II) six-ring oxygen environment in zeolite A and the corresponding ligand field spectrum using large cluster models that include all six that surround Al or Si tetrahedra terminated by either OH or H groups. The optimization of structures was done using density functional theory that employed a nonlocal method. Results indicate that the observed splitting of the main band in the spectrum is caused by the presence of asymmetric coordination sites.

In this work, the impact of a tungsten oxide (WO 3 ) seed and capping layer for ferroelectric La-doped (Hf, Zr)O 2 (La:HZO) based capacitors, designed with back-end-of-line (BEOL) compatibility, is systematically investigated. The WO 3 capping layer supplies oxygen to the La:HZO layer throughout the fabrication process and during device cycling. This facilitates the annihilation of oxygen vacancies (V o ) within the La:HZO layer, thereby stabilizing its ferroelectric orthorhombic phase and resulting in an increase of the remanent polarization (P r ) value in the capacitor. Moreover, the effectiveness of the WO 3 capping layer depends on the seed layer of the HZO film, suggesting that proper combination of the seed and capping layers should be employed to maximize the ferroelectric response. Finally, a TiN/TiO 2 seed layer/La:HZO/WO 3 capping layer/TiN capacitor is successfully fabricated and optimized by a complete set of atomic layer deposition (ALD) processes, achieving a superior 2P r value and endurance value of more than 10 9 cycles at an electric field of 2.5 MV/cm. The WO 3 capping layer is anticipated to offer a viable solution for doped HZO capacitors with reduced thickness, addressing the challenge of elevated V o levels that favor the tetragonal phase and result in low 2P r values.

Recently, a step-flow growth mode has been proposed to break the inherent molybdenum disulfide (MoS 2 ) crystal domain bimodality and yield a single-crystalline MoS 2 monolayer on commonly employed sapphire substrates. This work reveals an alternative growth mechanism during the metal-organic chemical vapor deposition (MOCVD) of a single-crystalline MoS 2 monolayer through anisotropic 2D crystal growth. During early growth stages, the epitaxial symmetry and commensurability of sapphire terraces rather than the sapphire step inclination ultimately govern the MoS 2 crystal orientation. Strikingly, as the MoS 2 crystals continue to grow laterally, the sapphire steps transform the MoS 2 crystal geometry into diamond-shaped domains presumably by anisotropic diffusion of ad-species and facet development. Even though these MoS 2 domains nucleate on sapphire with predominantly bimodal 0 and 60° azimuthal rotation, the individual domains reach lateral dimensions of up to 200 nm before merging seamlessly into a single-crystalline MoS 2 monolayer upon coalescence. Plan-view transmission electron microscopy reveals the single-crystalline nature across 50 μm by 50 μm inspection areas. As a result, the median carrier mobility of MoS 2 monolayers peaks at 25 cm 2 V -1 s -1 with the highest value reaching 28 cm 2 V -1 s -1 . This work details synthesis-structure correlations and the possibilities to tune the structure and material properties through substrate topography toward various applications in nanoelectronics, catalysis, and nanotechnology. Moreover, shape modulation through anisotropic growth phenomena on stepped surfaces can provide opportunities for nanopatterning for a wide range of materials.