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Structure and Constitution of Dichloro(tetraalkylcyclobutadiene)platinum(II) Complexes Hexachloroplatinic acid reacts in n-butanol with alkylsubstituted acetylenes RC≡CR (R = Me, Et) to give [PtCl2(C4R4)] (R = Me ( 1 ), R = Et ( 2 )). The X-ray structure analysis of 1 (C2/m; a = 1 370.3(2), b = 1 128.3(1), c = 691.21(7) pm, β = 96.10(1)α; Z = 4) shows that 1 is monomeric and not dimeric as was described in the literature. Furthermore, 1 and 2 were extensively studied by i.r., Raman, and n.m.r. spectroscopical investigations.  相似文献   

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The luminescence spectra of alkali tetrakis(dibenzoylmethido)europate(III) complexes in the crystalline state at 77°K have been measured in the spectral region 510–640 nm. The spectra show the existence of different modifications of these compounds. The spectra of the β-forms are consistent with a site symmetry D2 at the Eu(III) ion, the spectra of the corresponding α-forms with a site symmetry D4. A conversion from the β-form into the α-form on heating is observed in some cases. The conversion involves a change from dodecahedral into antiprismatic coordination around the Eu(III) ion.  相似文献   

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The Bromination of Push-Pull-Olefins. II. Structure Elucidation of the Bromination Products Bromination of 3-dialkylamino-acroleins 1a , b as well as of 4-dialkylamino-3-buten-2-ons 1c , d gives O-protonated produkts 2 with all-trans configuration of the (N? C? C? C? O)-skeleton. The structure of these hydrobromides 2 is confirmed by 1H- as well as by 13C-NMR. evidence.  相似文献   

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The analysis of the luminescence spectra of the pyridinium hexahalogeno complexes of europium(III) (PyH)3EuCl6 and (PyH)3EuBr6 is in accordance with the presence of a weakly distorted octahedral symmetry at the rare earth site. The parameters calculated from the splitting of the 7F2-level, \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm B}_{{\rm 40}} {\rm (EuCl}_{\rm 6} {\rm - - -) = 159 \pm 4 und B}_{{\rm 40}} {\rm (EuBr}_{\rm 6} {\rm - - -) = 152 \pm 4 cm}^{- {\rm 1}} {\rm,} $\end{document} are about four to five times larger than the parameters calculated theoretically from the electrostatic point-charge model.  相似文献   

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Sodium hexafluoromanganate(III) has been synthesized by heating equimolecular quantities of Na2MnF5 and NaF in argon atmosphere. The compound is monoclinic witha=5.56 (1) Å,b=5.84 (1) Å,c=8.10 (2) Å, =90.7 (2) andZ=2. It is a high spin complex with eff and the deformation of the octahedra is evident from its IR-spectra. Two enantiotropic transitions (at 562 and 653°C) and the melting point at 800°C have been observed.

8. Mitt.: Mh. Chem.106, 483 (1975).  相似文献   

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Zusammenfassung Die vor kurzem vonN. Schönberg aufgeklärten Strukturen von TiP, -ZrP, -TaP, MoP und WP werden bestätigt.Im System Ti–As treten mehrere intermediäre Phasen auf. Bei der ungefähren Zusammensetzung TiAs wurden zwei Phasen identifiziert. Eine der beiden kristallisiert im NiAs-Typ mit den Gitterkonstanten:a=3,63k X · E,c=6,14k X · E undc/a=1,69. Die zweite ist isotyp zu TiP und hat die Gitterkonstanten:a=3,64k X · E,c=12,28 k X · E undc/a=3,38. Ihr Aufbau steht in unmittelbarem Zusammenhang.  相似文献   

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