Publications by authors named "Martin Clemen"

The fragmentation behavior of N, N-diethylamino-substituted azobenzene derivatives is investigated by high-resolving mass spectrometry using a Fourier transform ion cyclotron resonance mass spectrometer. Former investigations by photodissociation as well as collision-induced dissociation experiments used to induce a loss of CH from the diethylamino group. The position of the additional proton in [M + H] ions is important due to the sequences of radical fragmentation reactions.

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The fragmentation reactions of Rhodamine B have been investigated by the use of electrospray ionization mass spectra in a high mass resolving ion cyclotron resonance mass spectrometer. Using high resolution, it could be shown that the loss of 44 mass units from the molecular ion is due to propane; the measured masses were inconsistent with loss of carbon dioxide. These conclusions are supported using deuterium-labeled Rhodamine B.

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Xanthene dyes such as rhodamine B undergo an interesting mass-spectrometric fragmentation reaction that eliminates small neutral alkanes such as propane. This fragmentation reaction has been investigated in a Fourier transform ion cyclotron mass spectrometer by means of laser photodissociation with visible light as well as by collision-induced dissociation. Different isotopically labeled decarboxyrhodamine B compounds were used to investigate the fragmentation mechanism.

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