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961.
Let G = (V, E) be a simple undirected graph. N(G) = (V, E N ) is the neighborhood graph of the graph G, if and only if $$E_N = \{\{a,b\}\,|\, a \neq b\,\wedge\,\exists\, x \, \in V: \{x,a\} \in E \, \wedge \, \{x,b\} \in E \}.$$ We present several structural properties of N(G) and characterize the hamiltonicity of N(G) by means of chords of a hamiltonian cycle in G. 相似文献
962.
Mauro Castellani Ingo Salzmann Philippe Bugnon Shuwen Yu Martin Oehzelt Norbert Koch 《Applied Physics A: Materials Science & Processing》2009,97(1):1-9
We report on the structural and electronic interface formation between ITO (indium-tin-oxide) and prototypical organic small
molecular semiconductors, i.e., CuPc (copper phthalocyanine) and α-NPD (N,N′-di(naphtalen-1-yl)-N,N′-diphenyl-benzidine). In particular, the effects of in situ oxygen plasma pretreatment of
the ITO surface on interface properties are examined in detail: Organic layer-thickness dependent Kelvin probe measurements
revealed a good alignment of the ITO work function and the highest occupied electronic level of the organic material in all
samples. In contrast, the electrical properties of hole-only and bipolar organic diodes depend strongly on the treatment of
ITO prior to organic deposition. This dependence is more pronounced for diodes made of polycrystalline CuPc than for those
of amorphous α-NPD layers. X-ray diffraction and atomic force microscopic (AFM) investigations of CuPc nucleation and growth evidenced a
more pronounced texture of the polycrystalline film structure on the ITO substrate that was oxygen plasma treated prior to
organic layer deposition. These findings suggest that the anisotropic electrical properties of CuPc crystallites, and their
orientation with respect to the substrate, strongly affect the charge carrier injection and transport properties at the anode
interface. 相似文献
963.
Patrick Pingel Achmad Zen Dieter Neher Ingo Lieberwirth Gerhard Wegner Sybille Allard Ullrich Scherf 《Applied Physics A: Materials Science & Processing》2009,95(1):67-72
Layers made from soluble low molecular weight polythiophene PQT-12 with low polydispersity exhibit a highly ordered structure
and charge-carrier mobilities of the order of 10−3 cm2/(V s), which we attribute to its proximity to monodispersity. We propose that polydispersity is a decisive factor with regard
to structure formation and transport properties of soluble low molecular weight polythiophenes.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users. 相似文献
964.
965.
Jan Steinheimer Ingo Augustin Takehiko Saito 《Progress in Particle and Nuclear Physics》2009,62(2):313-317
The project of the international Facility for Antiproton and Ion Research (FAIR), co-located to the GSI facility in Darmstadt, was officially started on November 7, 2007. An investment of about 1 billion euro will permit new physics programs in the areas of low and medium energy antiproton research, heavy ion physics complementary to LHC, as well as in nuclear structure and astrophysics. The facility will comprise about a dozen accelerators and storage rings, which will enable simultaneous operations of up to four different beams. 相似文献
966.
In an attempt to synthesize LiEu3S3[SiS4] utilizing elemental europium and sulfur as well as SiS2 and an excess of LiCl as flux and lithium source, dark red, platelet‐shaped single crystals of Li3Eu6[SiS4]4 were obtained. This new compound crystallizes in the cubic space group I4 3d (a = 1369.22(5) pm) with four formula units per unit cell. Both the Li+ and the Si4+ cations are surrounded by four sulfide anions. The [SiS4]4– tetrahedra show merely a slight trigonal distortion, while the [LiS4]7– units are best described as flattened bisphenoids. The europium cations exhibit an eightfold, rather irregular coordination environment by eight S2– anions and have to be regarded mixed‐valent with a +2:+3 charge‐ratio of 5:1 in order to gain electroneutrality. The lack of an inversion center is caused by the [SiS4]4– tetrahedra being stacked exclusively top up along [111] in this acentric crystal structure. 相似文献
967.
Mario Schleep Clarissa Hettich Jana Maren Glatz Daniel Kratzert Witali Beichel Jennifer Velzquez Rojas Harald Scherer Ingo Krossing 《无机化学与普通化学杂志》2019,645(3):301-308
Surprisingly little is known about fluorinated tin(II) alkoxides. Here the synthesis and characterization of Sn(ORF)2 [ORF = OC(CF3)3] and the crystal structures of its adducts with phenanthroline and dppe are reported. In addition, its ate complex [Sn(ORF)3]– was synthesized with lithium or sodium as cation and as acetonitrile adduct. The thermolytic behavior of both, the alkoxide and the lithium stannate(II), was investigated together with first electrochemical measurements of Li[Sn(ORF)3]. 相似文献
968.
Upon reacting SeCl4 with Me3Si–F–Al(ORF)3, the selenonium salt SeMeCl2[al‐f‐al] ( 1 ) {[al‐f‐al]– = [F[Al(OC(CF3)3)3]2]–} was obtained and characterized by NMR, IR, and Raman spectroscopy as well as single crystal XRD experiments. Despite the [SeX3]+ (X = F, Cl, Br, I) and [SeR3]+ salts (R = aliphatic organic residue) being well known and thoroughly studied, the mixed cations are scarce. The only previous example of a salt with the [SeMeCl2]+ cation is SeMeCl2[SbCl6], which was never structurally characterized and is unstable in solution over hours. Only 1H‐NMR studies and IR spectra of this compound are known. The unexpected use of Me3Si–F–Al(ORF)3 as a methylating agent was investigated via DFT calculations and NMR experiments of the reaction solution. The reaction of SeCl3[al‐f‐al] with Me3Si‐Cl at room temperature in CH2Cl2 proved to yield the same product with Me3Si–Cl acting as a methylating agent. 相似文献
969.
Domenik Schleier Engelbert Reusch Lisa Lummel Dr. Patrick Hemberger Prof. Dr. Ingo Fischer 《Chemphyschem》2019,20(19):2413-2416
Iodine oxides appear as reactive intermediates in atmospheric chemistry. Here, we investigate IO and HOI by mass-selective threshold photoelectron spectroscopy (ms-TPES), using synchrotron radiation. IO and HOI are generated by photolyzing iodine in the presence of ozone. For both molecules, accurate ionization energies are determined, 9.71±0.02 eV for IO and 9.79±0.02 eV for HOI. The strong spin-spin interaction in the 3Σ− ground state of IO+ leads to an energy splitting into the Ω=0 and Ω=±1 sublevels. Upon ionization, the I−O bond shortens significantly in both molecules; thus, a vibrational progression, assigned to the I−O stretch, is apparent in both spectra. 相似文献
970.
Ingo Buchholz 《Zeitschrift für Physik A Hadrons and Nuclei》1969,227(5):440-452
There exists a quantitative connection between penetration depth of primary electrons, the maximum escape depth of secondary electrons and the position of the maximum of the yield curve if one assumes: (1) the maximum of the yield curve is determined by an energyE p max of the primary electrons where the maximum penetration depth of primary electrons equals the maximum escape depth of the secondary electrons; and (2) the maximum escape depth of secondary electrons is given by 10 atomic layers for all metals investigated as it has been found earlier by Mayer and Hölzl for potassium. These assumptions are confirmed experimentally by measurements of yield curves and energy distributions at defined conditions and by variation of several parameters as temperature, contamination of the surface, surface roughness, evaporation conditions, and angle of incidence of the primary electrons. 相似文献