Search results for "ddc:5"
showing 10 items of 1717 documents
High-pressure phase ofLaPO4studied by x-ray diffraction and second harmonic generation
2016
The pressure-induced phase transition of monazite-type ${\mathrm{LaPO}}_{4}$ at $\ensuremath{\approx}26$ GPa is studied by single-crystal x-ray diffraction and second harmonic generation (SHG) up to 31 GPa. The structure of the postmonazite phase of ${\mathrm{LaPO}}_{4}$ has been obtained and it is shown that it corresponds to a post-barite-type structure with an acentric space group $P{2}_{1}{2}_{1}{2}_{1}$. A strong increase of the SHG signal at the transition confirms that the high-pressure polymorph is noncentrosymmetric. The phase transition involves a significant discontinuous decrease of the unit-cell volume by 6%, which is mainly due to a strong contraction of the $a$ lattice parame…
High-resolution hard-x-ray photoelectron diffraction in a momentum microscope—the model case of graphite
2019
New journal of physics 21(11), 113031 - (2019). doi:10.1088/1367-2630/ab51fe
Backward transition radiation in the extreme ultraviolet region as a tool for the transverse beam profile diagnostic
2014
The present article summarizes the results of two experiments which were performed to study the radiation properties of backward transition radiation (BTR) in the extreme ultraviolet (EUV) region. This wavelength region is of particular interest for transverse beam profile imaging, because the spatial resolution is improved as a result of the reduced contribution in the imaging process of the fundamental diffraction limit. In addition, the influence of coherent effects in the transition radiation emission process, which have been observed in the visible region, might be mitigated. The first experiment, dedicated to the investigation of the BTR angular characteristics, indicates that the rad…
A Next‐Generation Air‐Stable Palladium(I) Dimer Enables Olefin Migration and Selective C−C Coupling in Air
2020
Abstract We report a new air‐stable PdI dimer, [Pd(μ‐I)(PCy2 tBu)]2, which triggers E‐selective olefin migration to enamides and styrene derivatives in the presence of multiple functional groups and with complete tolerance of air. The same dimer also triggers extremely rapid C−C coupling (alkylation and arylation) at room temperature in a modular and triply selective fashion of aromatic C−Br, C−OTf/OFs, and C−Cl bonds in poly(pseudo)halogenated arenes, displaying superior activity over previous PdI dimer generations for substrates that bear substituents ortho to C−OTf.
A polymeric two-dimensional mixed-metal network. Crystal structure and magnetic properties of {[P(Ph)4][MnCr(ox)3]}
1994
Abstract The mixed-metal ferromagnet {[P(Ph) 4 ][MnCr(ox) 3 ]} n , where Ph is phenyl and ox is oxalate, has been prepared and a two-dimensional network structure, extended by Mn(II)-ox-Cr(III) bridges, has been determined from single crystal X-ray data. Crystal data: space group R 3 c , a = b =18.783(3), c =57.283(24) A, α=β=90, γ=120°, Z =24 (C 30 H 20 O 12 PCrMn). The magnetic susceptibility data obey the Curie-Weiss law in the temperature range 260–20 K with a positive Weiss constant of 10.5 K. The temperature dependence of the molar magnetization exhibits a magnetic phase transition at T c =5.9 K. The structure is discussed in relation to the strategy for preparing molecular based ferr…
Shear moduli of two dimensional binary glasses
2012
The shear moduli of two-component glasses in two dimensions are studied within mode coupling theory. Varying the concentration, strong mixing effects are observed along the glass transition lines for two interaction potentials. Nonoverlapping disks with size ratios between 0.3 and 0.9, and point particles interacting with (magnetic) dipoles of strength ratio between 0.1 and 0.6 are considered. Equilibrium structure factors (partially obtained from Monte Carlo simulations) and glass form factors, and perturbative calculations show that a softening of the elastic shear constant of glass upon adding another component arises from a dilution effect of the majority component. For very disparate m…
Real-space grids and the Octopus code as tools for the development of new simulation approaches for electronic systems.
2015
This Open Access Article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
First Measurement of Transverse-Spin-Dependent Azimuthal Asymmetries in the Drell-Yan Process
2017
The first measurement of transverse-spin-dependent azimuthal asymmetries in the pion-induced Drell-Yan (DY) process is reported. We use the CERN SPS 190 GeV/$c$, $\pi^{-}$ beam and a transversely polarized ammonia target. Three azimuthal asymmetries giving access to different transverse-momentum-dependent (TMD) parton distribution functions (PDFs) are extracted using dimuon events with invariant mass between 4.3 GeV/$c^2$ and 8.5 GeV/$c^2$. The observed sign of the Sivers asymmetry is found to be consistent with the fundamental prediction of Quantum Chromodynamics (QCD) that the Sivers TMD PDFs extracted from DY have a sign opposite to the one extracted from semi-inclusive deep-inelastic sc…
Erratum to: DYTurbo: fast predictions for Drell–Yan processes
2020
The European physical journal / C 80(5), 440 (2020). doi:10.1140/epjc/s10052-020-7972-0
DYTurbo: fast predictions for Drell–Yan processes
2019
The European physical journal / C 80(5), 251 (2020). doi:10.1140/epjc/s10052-020-7757-5