Die statische Stabilit�t von Schenkelpolmaschinen im Verbundbetrieb

Abstract

l]bersicht: Es wird eine MeLhode angegeben, welche es gestattet, die EigenwerL-M~Lrix dieses Problems aus der Impedanzmatrix des gegebenen Netzes, dell Synchronreaktanzen X d und Xq und den (komplexen) Polradspannungen der Generatoren zu ermitteln. Vorbemerkungen

Lithium and Ytterbium Aminotroponate Complexes

“…Since no solvent molecules are bound to the lithium atoms, they are -as a result of the hexamerization -tetracoordinated. Similar hexameric structures were observed before in some lithium alkoxides such as lithium phenolate, [25] [LiCϵCSiMe 2 C 6 H 4 OMe] 6 , [26] and the thiophene derivative [LiOSiMe 2 (2-C 4 H 3 S)] 6 . [27] The 1 H and 13 C{ 1 H} NMR spectra of compound 1 show the expected set of signals for the (iPrAT) -ligand.…”

“…[29] Treatment of (iPrAT)H with an excess of nBuLi in toluene followed by crystallization from hot toluene resulted in the hexameric species [(iPrAT)Li] 6 (1) (Scheme 2). The new complex has been characterized by standard analytical/spectroscopic techniques, and the solidstate structure was established by single-crystal X-ray diffraction.…”

“…Herein we report on the synthesis of a hexameric lithium 2-(isopropylamino)troponate cluster [(iPrAT)Li] 6 [iPrAT = 2-(isopropylamino)troponate] and the further reaction of this compound with anhydrous ytterbium trichloride.…”

“…[1,2] In this context, functionalized chelating diamides have been extensively studied as ligands [3] giving highly active precatalysts comparable to the well-established group 4 metallocenes. [4] In lanthanide chemistry anionic nitrogen-based bidentate ligand systems such as diazadienes, [5] benzamidinates, [6,7] guanidinates, [8,9] amido ligands, [10] and other combinations of nitrogen and oxygen atoms [11] were used as cyclopentadienyl replacements to increase the electrophilicity of the metal center and to create a different steric environment at the reactive site. In a recent review article, Piers and Emslie presented a most useful classification of non-cyclopentadienyl ancillaries in organo group 3 metal chemistry covering bi-, tri-, tetra-, and polydentate amido and alkoxido ligands.…”

TiIV Complexes with Novel, Chiral, Tridentate Amido‐Amidinate or Monoanionic, Didentate Amidinate Ligands

“…[1,2] For group 4 transition metals, amidinates have been used as ancillary ligands in olefin polymerization catalysis. [3,4] Recently, several groups have reported the introduction of an additional electron-donor amine or pyridine functionality thus forming six-electron-donor, three-coordinate ligands that are close analogues of Cp ligands.…”