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61.
Savjani N Lancaster SJ Bew S Hughes DL Bochmann M 《Dalton transactions (Cambridge, England : 2003)》2011,40(5):1079-1090
Compounds of the new tetrafluorophthalimido anion, [C(6)F(4)(CO)(2)N](-), are readily accessible by treatment of tetrafluorophthalimide with either LiNPr(i)(2) or mixtures of NEt(3) and Me(3)ECl (E = Si or Sn), to give C(6)F(4)(CO)(2)N-X (X = Li 3, SiMe(3)4, and SnMe(3)5). The reaction of the trimethylsilyl derivative 4 with AgF leads cleanly to the ion pair complex [Ag(NCMe)(2)][Ag(N(CO)(2)C(6)F(4))(2)] (6·2MeCN), which contains a linear [Ag{N(CO)(2)C(6)F(4)}(2)](-) anion and a tetracoordinate Ag(+) cation. Compound 6 reacts with iodine to give the N-iodo compound C(6)F(4)(CO)(2)NI 7, which crystallises as an acetonitrile adduct. Treatment of 6 with LAuCl affords LAu{N(CO)(2)C(6)F(4)} (L = Ph(3)P 8a, Cy(3)P 8b, or THT 9), whereas the reaction with AuCl in acetonitrile affords the heterobinuclear compound [Ag(MeCN)(2)][Au{N(CO)(2)C(6)F(4)}(2)]·MeCN (10·3MeCN). The tetrafluorophthalimido ligand is not readily displaced by donor ligands; however, the addition of B(C(6)F(5))(3)(Et(2)O) to a diethyl ether solution of 8a leads to the salt [Au(PPh(3))(2)][N{COB(C(6)F(5))(3)}(2)C(6)F(4))] 11. The analogous reaction of (THT)Au{N(CO)(2)C(6)F(4)} with B(C(6)F(5))(3) in toluene in the presence of excess norbornene (nb) gives [Au(nb)(3)][N{COB(C(6)F(5))(3)}(2)C(6)F(4))] 12. Compounds 11 and 12 contain a new non-coordinating phthalimido-bridged diborate anion with O-bonded boron atoms. The crystal structures of compounds 2-11 are reported. 相似文献
62.
Lansbergen GP Rahman R Verduijn J Tettamanzi GC Collaert N Biesemans S Klimeck G Hollenberg LC Rogge S 《Physical review letters》2011,107(13):136602
We report the observation of lifetime-enhanced transport (LET) based on perpendicular valleys in silicon by transport spectroscopy measurements of a two-electron system in a silicon transistor. The LET is manifested as a peculiar current step in the stability diagram due to a forbidden transition between an excited state and any of the lower energy states due to perpendicular valley (and spin) configurations, offering an additional current path. By employing a detailed temperature dependence study in combination with a rate equation model, we estimate the lifetime of this particular state to exceed 48 ns. The two-electron spin-valley configurations of all relevant confined quantum states in our device were obtained by a large-scale atomistic tight-binding simulation. The LET acts as a signature of the complicated valley physics in silicon: a feature that becomes increasingly important in silicon quantum devices. 相似文献
63.
We investigate the Kondo effect and spin blockade observed in a many-electron quantum dot and study the magnetic field dependence. At lower fields, a pronounced Kondo effect is found, which is replaced by the spin blockade at higher fields. In an intermediate regime, both effects are visible. We make use of this combined effect to gain information about the internal spin configuration of our quantum dot. We find that the data cannot be explained assuming regular filling of electronic orbitals. Instead, spin polarized filling seems to be probable. 相似文献
64.
Nikolaos Kaplaneris Torben Rogge Rongxin Yin Hui Wang Giedre Sirvinskaite Lutz Ackermann 《Angewandte Chemie (International ed. in English)》2019,58(11):3476-3480
Bioorthogonal C?H allylation with ample scope was accomplished through a versatile manganese(I)‐catalyzed C?H activation for the late‐stage diversification of structurally complex peptides. The unique robustness of the manganese(I) catalysis manifold was reflected by full tolerance of sensitive functional groups, such as iodides, esters, amides, and OH‐free hydroxy groups, thereby setting the stage for the racemization‐free synthesis of C?H fused peptide hybrids featuring steroids, drug molecules, natural products, nucleobases, and saccharides. 相似文献
65.
Let Pn, nIN{0}, be probability measures on a-fieldA; fn, nIN{0}, be a family of uniformly boundedA-measurable functions andA
n, nIN, be a sequence of sub--fields ofA, increasing or decreasing to the-fieldA
o. It is shown in this paper that the conditional expectations converge in Po-measure to with k, n, m , if Pn|A, nIN, converges uniformly to Pn|A and fn, nIN, converges in Po-measure to fo. 相似文献
66.
67.
In this Letter we report the observation of K lines (representing collectively, Kossel and Kikuchi lines) produced by monochromatic thermal neutrons interacting with a KDP (potassium dihydrogen phosphate) single crystal. Since K lines contain phase information, these observations establish the experimental basis for direct crystallographic phasing of atomic structures containing incoherent scatterers, such as hydrogen, via thermal neutron "inside source" holography. 相似文献
68.
It is proven that in large classes of topological spaces each real-valued continuous function on aG
δ-setG has an extension to the whole space which is continuous exactly at the points ofG. AmongG
δ-spaces this property characterizes the almost resolvable normal spaces. 相似文献
69.
70.
BiN could be produced by reaction of active nitrogen with Bi-atoms. It was stabilized in Kr at 10 K (ω = 737 cm?1). The IR frequencies of group V nitrenes are compared and yield with ωe = 1030 cm?1 for AsN. 相似文献