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Abstract.A triple stage hybrid mass spectrometer was scanned for the trapping of the reaction intermediates of the over-all loss of two CsI-moieties from size-selected caesium iodide cluster ions of the general formula Cs (CsI). + . In addition to appropriate MS/MS/MS-methods an electrically floated collision cell has been applied to trap intermediates of unimolecular and collision-induced evaporations. In comparison with other experimental findings the features of the evaporation mechanism are discussed.

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Es wird über EPR‐Untersuchungen an den 4 t 2g5‐„low spin”︁‐Nitrosyltechnetium(II)‐Komplexen (Bu4N)2[Tc(NO)Cl5], (Bu4N)[Tc(NO)Br4], (Bu4N)[Tc(NO)I4] und (Ph4As)2 [Tc(NO)(NCS)5] berichtet. Anhand der EPR‐Parameter g̃, ÃTc sowie Ligandenhyperfeinstrukturdaten werden die Bindungsverhältnisse analysiert. Die isotropen Parameter g0 und a 0Tc zeigen eine definierte Abhängigkeit von der Zusammensetzung der Koordinationssphäre und erweisen sich für die Charakterisierung von Gemischtligandkomplexen als geeignet. Die Bildung von Gemischtligandkomplexen wird bei Ligandenaustauschreaktionen an [Tc(NO)Cl5]2− und [Tc(NO)Br4]−, auch unter Einbeziehung von ungesättigten Dichalkogenoliganden, untersucht.

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Some partial synthetic amino acid ((S)‐alanine, (S)‐leucine, (S)‐isoleucine, (S)‐aspartic acid, (S)‐glutamic acid, (S)‐phenylalanine, (S)‐ and (R)‐valine) conjugates of the plant growth regulator (‐)‐jasmonic acid (JA) were investigated as methyl esters by capillary gas chromatography/mass spectrometry. By gas chromatographic data (retention indices) as well as by mass spectral behaviour all these substances can be differentiated unequivocally. In addition, the distinction between the leucine and isoleucine JA conjugates was carried out by mass‐analysed ion kinetic energy spectroscopy (tandem mass spectrometry). Based on this some naturally occurring (S)‐isoleucine conjugates of (‐)‐JA, (+)‐7‐iso‐JA and related compounds as well as the (S)‐leucine and (S)‐phenylalanine conjugates of (‐)‐JA could be identified from extracts of the broad bean Vicia faba L.