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1.
I.R. and N.M.R. Spectroscopic Investigations on Substituent Effects in Siloxy and Alkoxysilanes Siloxy and alkoxysilanes of the types (RMe2SiO)3SiH, (RMe2CO)3SiH, (Me3–nPhnSiO)m(Me3SiO)3–mSiH (m = 1—3, n = 1—3), and Me3–n(RMe2SiO)nSiH (n = 1—3) have been prepared. The influence of the substituent effects through the (Me2)Si? O- a (Me2)C? O- group on the Si? H band is approximately equal.  相似文献   

2.
Spectroscopie Investigations on R? C6H4O(CH3)2SiF Compounds The i.r. and Raman spectra of a number of R? C6H4O(CH3)2SiF compounds (R = H, CH3, CH3O, Cl, Br, NO2, NH2) have been recorded. The intramolecular and intermolecular interactions were discussed by means of ν SiF, ν Si? O? (C), ν C? O? (Si) and νs SiC2 vibrations.  相似文献   

3.
Spectroscopic Investigation of Allylboron Compounds The data of the IR and RAMAN spectra of triallyl-, tricrotyl- and trimethallyl-boron and their coordination compounds are listed and the vibrations assigned. In the discussion of the results data of tri-ethylboron are included.  相似文献   

4.
The RAMAN and IR spectra (400–4000 cm?1) of (CH3)3GeF, (C2H5)3GeF, (n-C3H7)3GeF, (n-C4H9)3GeF in the solid, liquid and gaseous state, and of (C6H5)3GeF in the solid and dissolved state are recorded and the frequencies almost completely assigned. The spectra show in the region 500–700 cm?1 a relatively high shift of the frequencies, due to intermolecular interaction.  相似文献   

5.
Inhaltsübersicht. Es werden die Ergebnisse der röntgenographischen, ligandenfeldspektro-skopischen sowie IR-spektroskopischen Untersuchungen des Mischkristallsystems Sr2–xBaxNi TeO6 mitgeteilt und mit denen entsprechender Untersuchungen der Mischkristalle Ba2NiTexW1–xO6 und Ba2NixMg1–xTeO6 verglichen. In diesen Systemen ist mit wachsendem x ein Übergang von der Elpasolith- über die hexagonale BaTiO3-(6-Schichten-) zur hexagonalen Ba2NiTeO6-(12-Schichten-) Struktur zu beobachten. Im Falle der Verbindungen Sr2–xBaxNiTeO6 konnten zusätzlich bei kleinen x-Werten Übergänge von der monoklinen Struktur (Sr2NiTeO6) über eine tetragonale Variante der Elpasolithstruktur zum kubischen Gitter gefunden werden. Mittels bei 4 K und 293 K aufgenommener Ligandenfeldspektren wird die Auswirkung der strukturellen Veränderungen beim Ubergang von der geordneten Elpasolithstruktur zu den hexagonalen Varianten auf die Symmetrie und die Bindungsverhältnisse der NiO6-Oktaeder verfolgt, während die IR-Spektren zusätzlich die Symmetrieverände-rungen der TeO6-Oktaeder erkennen lassen. Schließlich konnte mit Hilfe beider spektroskopischen Methoden Aussagen über die Kationenverteilung in den hexagonalen Phasen gemacht werden. Spectroscopic and Structural Investigations on Hexagonal Elpasolites The results of X-ray as well as ligand field and i.r. spectroscopic investigations of the mixed crystal series Sr2–xBaxNiTeO6 are reported and compared with those of Ba2NiTexW1–xO6 and Ba2NixMg1–xTeO6. In these compounds transitions from the elpasolite to the hexagonal BaTiO6 (6 layers) and finally to the hexagonal Ba2NiTeO6 (12 layers) structure are observed with increasing x. In addition a change from the monoclinic structure (Sr2NiTeO6 type) to a tetragonal variant of the elpasolite lattice and finally to the cubic structure is found in the mixed crystal series Sr2–xBaxNiTeO6 at low x values. The influence of these structural changes on the symmetry and the bonding within the NiO6 polyhedra is studied by the parameters taken from the 4 K and 293 K ligand field spectra. In addition the i.r. spectra give information with respect to the symmetry of the TeO6 polyhedra. Finally the cation distribution in the hexagonal phases could be deduced from the spectroscopic data.  相似文献   

6.
Spei  M.  Heidemann  G. 《Colloid and polymer science》1967,216(1):269-277
Colloid and Polymer Science - Mit Hilfe der NIR-Spektroskopie und der UV-Spektroskopie wurde versucht, die Ausbildung hydrophober Bindungen in wäßrigen Lösungen einheitlicher,...  相似文献   

7.
8.
The mass, IR- and NMR-spectra of 18 compounds were interpreted; one of these compounds has been15N-labelled.Fragmentation processes give evidence that azo- and hydrazone-tautomeres are present in the gaseous state. IR-and NMR-spectroscopic investigations show, that the phenyl-hydrazones as solids and in solution exist as bis chelated (Z)-isomers only. An approximately linear relationship is given between the chemical shifts of NH-Protons and pK B-and Hammett -values resp.

Mit 5 Abbildungen

M. Grote, Dissertation, Ruhr-Universität Bochum, 1975.  相似文献   

9.
Zusammenfassung Eine Reihe von Metallkomplexen des 2,5-Dibenzoyl-3,4-dihydroxy-selenophens wurden spektroskopisch untersucht. Das Verhalten des Wismutkomplexes und die Möglichkeiten einer spektrophotometrischen Wismutbestimmung auf diesem Wege wurden eingehend studiert.
Summary A spectroscopic examination was made of a series of metal complexes of 2,5-dibenzoyl-3,4-dihydroxyselenophen. The behavior of the bismuth complex and the possibilities of a spectrophotometric method of determining bismuth in this manner were studied thoroughly.


Herrn Univ.-Prof. Dr.Hans Lieb zum 80. Geburtstag gewidmet.  相似文献   

10.
Spectroscopic and X-Ray Structural Investigations on Dichloromethyl Mercury Compounds Bis(dichloromethyl)mercury, Hg(CHCl2)2, and mixed alkyl compounds RHgCHCl2 (with R = CH3, C2H5) have been synthesized by known methods from CH2Cl2, lithium butanide and HgCl2, CH3HgCl or C2H5HgCl, respectively. The 1H-, 13C-NMR as well as the IR and Raman spectra of the liquid alkyls RHgCHCl2 and the high melting Hg(CHCl2)2 have been measured and assigned. According to the X-ray structure determination Hg(CHCl2)2 crystallizes in the monoclinic space group P21/c with 4 non-symmetric molecules per unit cell (R = 0.046).  相似文献   

11.
Zusammenfassung Die Addukte von SiF4 mit 2 Molekülen NH3, ND3, N2H4 und CH3NH2 wurden IR- und Raman-spektroskopisch untersucht. Schwingungsspektren,19F-Breitband-KMR und chemische Eigenschaften stehen mit einercis-oktaedrischen Struktur im Einklang, in der vermutlich durch Dipol—Dipol-Wechselwirkungen einzelne Komplexmoleküle zu polymeren Einheiten zusammentreten.
Complexes of SiF4 with 2 molecules of NH3, ND3, N2H4, and CH3NH2 were investigated by IR and Raman spectroscopy. The results as well as19F broadline nmr and chemical properties support acis-octahedral structure. Probably dipol—dipol interactions are responsible for the association of the complex molecule. *** DIRECT SUPPORT *** A3615111 00003
  相似文献   

12.
13.
Spectroscopic Studies on Water-Methanol Solutions of Magnesium Sulphate in Near Infrared Region Spectroscopic studies on spectra of water-methanol solutions and water-methanol solutions of magnesium sulphate, unknown in literature, are presented. The influence of salt addition on the position of absorption maxima of water and methanol, as well as their intensity, was observed. The changes described were connected with interaction existing in tested systems.  相似文献   

14.
The electron impact induced cleavage of the oxygen-carbon (or oxygen-silicon) bond is accompanied by an intramolecular migration of the silyl function onto the oxygen. Details of the mechanism formally correspond with a dyotropic rearrangement.  相似文献   

15.
Zusammenfassung Es werden Hückel-MO-Rechnungen am Borazol und den B-Trihalogenoborazolen durchgeführt und die entsprechenden Parameter an den teils bekannten und teils gemessenen UV-Spektren geeicht. Die für diese Verbindungen bestimmten chemischen Verschiebungen der 11B- und 14N-Kernresonanz lassen sich mit den berechneten -Elektronendichten erklären.
Hückel-MO calculations are performed for Borazine and the B-Trihalogenoborazines; the parameters used are calibrated with the UV-spectra, which had either been measured here or obtained from the literature. The calculated -electron densities compare favorably well with the 11B- and 14N-nuclear magnetic resonances determined for the above mentioned compounds.

Résumé Le borazole et les B-trihalogenoborazoles sont calculés par la méthode de Hückel en utilisant des paramètres calibrés sur les spectres U.V. mesurés ou obtenus dans la littérature. Les densités électroniques sont en bon accord avec le déplacement chimique de N.M.R. de 11B et 14N déterminé pour les composés cidessus.


Herrn Professor Dr. H. Hartmann danken wir für sein stetes Interesse und die wohlwollende Förderung dieser Arbeit. Für die Hilfe bei der Aufnahme des Vakuum-UV-Spektrums von Fluoroborazol danken wir Herrn Diplom-Physiker E. Mohler.  相似文献   

16.
Mössbauer-spectrometric and Catalytic Investigations of the System Pt? Sn? η-Al2O3 Tin compounds on an Al2O3-carrier exhibit interactions with the carrier, their chemical properties are different from those of the carrier-free compounds. In reduced Pt? Sn? Al2O3 catalysts of different preparation there are different interactions between platinum and tin. Impregnation of the carrier with platinum-tin complexes gives vicinal locations of both compounds in socalled Pt? Sn ensembles. The modification of the electronic properties of a part of the platinum by tin in Pt? Sn? Al2O3 catalysts causes a decrease of the adsorption of hydrogen and of the activity in the dehydrogenation of cyclohexane, and an increase of the activity of dehydrocyclization of n-heptane.  相似文献   

17.
Spectroscopic and X-Ray Structure Investigations on Methylene Bridged Organoantimony Compounds The vibrational spectra of (Me2Sb)2CH2 and of the halogen derivatives (Me2Cl2Sb)2CH2 and (Me2Br2Sb)2CH2 (Me = CH3) have been measured and discussed. The i.r. and Raman data for liquid bis(dimethylstibino)methane are consistent with a mixture of two rotamers of Cs and C2v symmetry, respectively. For the halogen compounds only one form is spectroscopically proved. The X-ray structure determination of (Me2Cl2Sb)2CH2 · CH2Cl2 shows the monoclinic space group P21/n with a = 968.2; b = 1746.8; c = 982.2 pm and β = 91.95°. The structure was refined to an R-value of 0.038.  相似文献   

18.
Zusammenfassung Die elektronischen diffusen Reflexionsspektren bei Raumtemp. zwischen 7,5 und 28 kK und die magnetischen Susceptibilitäten bei 77°, 195° und 292° K wurden an einem erstmals dargestellten komplexen Nickel-Azid der Zusammensetzung K4Ni(N3)6 gemessen. Die Analyse des Absorptionsspektrums auf ligandenfeldtheoretischer Grundlage zeigt eine oktaedrische N3 -Umgebung des Ni2+. Aus der Rechnung ergeben sich der Kristallfeldparameter zu 8,3 kK und dieRacah-ParameterB zu 0,76 kK undC zu 3,17 kK. Das gegenüber dem Nur-Spin-Wert vergrößerte effektive magnetische Moment ist durch die Beimengung von Bahnmomentanteilen des angeregten3T2-Zustandes zum3A2-Grundterm des Ni via Spin—Bahn-Kopplung bedingt. Der große Wert für und die gleichzeitige starke Reduktion derRacah-Parameter sowie der Spin—Bahn-Kopplungskonstanten weisen auf eine Elektronendelokalisierung im Zentralion und Polarisationseffekte im Liganden hin. Dadurch wird die Überlappung erhöht und der kovalente Bindungsanteil im [Ni(N3)6]4–-Molekül verursacht, der wesentlich größer ist als im [NiF6]4–- und [Ni(H2O)6]2+-Molekül.
The electronic diffuse reflectance spectra at ambient temperature between 7,5 and 28 kK of a complex nickel azide prepared for the first time and having the composition K4Ni(N3)6 have been measured together with values of the magnetic susceptibility at 77°, 195° and 292° K. By ligand field analysis of the spectrum an octahedral N3 -environment around the Ni2+ was found. From the calculation the cubic crystal field parameter was determined to be 8,3 kK and the Racah parameters B=0,76 kK and C=3,17 kK. The effective magnetic moment was found to be larger than the spin-only value because of an orbital contribution of the excited3T2 state to the3A2 ground term of Ni2+ via spin-orbit coupling. The large crystal field splitting and the simultaneous large reduction of both the Racah parameters and the spin-orbit coupling constant are pointing at some delocalization among the d-electrons of the central ion and polarization effects within the ligands. Both effects are favorable for increasing overlapping and covalency within the [Ni(N3)6]4–-molecule, the latter effect being much larger in the azide than for instance in the [NiF6]4–- and [Ni(H2O)6]2+-molecule.


Mit 1 Abbildung  相似文献   

19.
The following p-substituted N,N-bis-trimethlsilyl anilines p-X? C6H4? N[Si(CH3)3]2 are prepared by silylation of free amines: X = H, CH3, C2H5, CH3O, CH3CO, F, Cl, Br, J, CN, C6HS, (CH3)3SiO, and [(CH3)3Si]2N, and the isotopic derivatives C6H5? 15N[Si(CH3)3]2 and C6D5N[Si(CH3)3]2. The vibrational spectra are reported and assigned. The molecular symmetry of p-[(CH3)3Si]2N? C6H4? N[Si(CH3)3]2 is determined. The influence of the mass of the substituents X on the positions of the νsSiNSi vibrational frequencies is discussed.  相似文献   

20.
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