Mass Spectral Study of Anthrone

The electron impact induced fragmentation of anthrone and its 10,1O-dideuterated analogue has been studied in the mass spectrometer using low and high resolution, as well as ion kinetic energy measurements. The most important process observed in the mass spectra is 105sof CO from the molecular ions with formation of ions of possible fluorenyl cation structure. Such ions, as shown earlier, undergo extensive hydrogen scrambling. In agreement with a fluorenyl cation structure, statistical loss of hydrogen in the fragmentation of anthrone is observed

Mass Spectral Fragmentation Study of Substituted 1,3-Diphenyl- 2-pyrazolines

The electron impact induced fragmentation of twenty two 1,3- -diphenyl-2-pyrazolines mono-, di- and trisubstituted in one or in both phenyl rings was studied by deuterium labelling, high and low resolution mass spectrometry, and ion kinetic energy spectroscopy. The fragmentation patterns are discussed taking into account especially the nature of the substituent and the position of substitution. The results, compared with those for the unsubstituted compound, showed that in general the phenyl ring substitution does not affect its fragmentation. The formation of stable quinoid-type ions directs many fragmentation pathways of methoxy substituted compounds

50 years of Mass Spectrometry at Rudjer Boskovic Institute

Dan je pregled aktivnosti i znanstvenih rezultata suradnika Laboratorija za kemijsku kinetiku (kasnije Laboratorija za kemijsku kinetiku i atmosfersku kemiju) Instituta Ruđer Bošković na području spektrometrije masa od 1959. do danas.An overview is given of activities and scientific results by coworkers of the Laboratory for Chemical Kinetics (later Laboratory for Chemical Kinetics and Atmospheric Chemistry) of the Rudjer Boskovic Institute in the field of mass spectrometry from 1959 to the present

LD FTMS Investigation of Rh(I) Complexes with Chiral 1,5-Bisnitrogen Ligands

Laser Desorption/Iomzation (LD/I) in combination with Fourier Transform Mass Spectrometry (FTMS) was applied to characterize and obtain molecular weight information on Rh(I) complexes with chiral 1,5-bisnitrogen ligands 1-

Gas-phase metallation reactions of porphyrins with metal monocations

The gas-phase reactions of octaethylporphyrin (H 2P, III) with 12 metal monocations, which were produced by laser ablation of Al, V, Cr, Fe, Ni, Nb, Mo, Hf, W, Re, Pt, and Au targets in an ICR-FTMS instrument, revealed three possible reaction pathways: (i) charge transfer; (ii) metal incorporation (ligation) with loss of H 2; and (iii) dimerization of the ligation product from pathway ii by addition of another porphyrin without further loss of H 2. The differences in metal behavior are discussed. The reaction of a mixture of hexaethyldimethylporphyrin (H 2P, I) and pentaethyltrimethylporphyrin (H 2P, II) with neat Fe + was also investigated; it was found that more than half of the Fe + reacts by charge exchange and that the lower-alkylated porphyrin (I), which has the higher ionization energy (IE), reacts more slowly in charge exchange but with the same rate in the both ligation and dimerization reactions as the higher alkylated porphyrin (H 2P, II)