Evaluation of laser desorbed transition-metal ions as analytical chemical ionization reagents by pattern recognition

Ten transition-metal ions are evaluated as chemical ionization reagents by use of pattern recognition. The data for the reactions of Sc/sup +/, Y/sup +/, La/sup +/, V/sup +/, Nb/sup +/, Ta/sup +/, Cr/sup +/, Fe/sup +/, Co/sup +/, and Cu/sup +/ with 11 ketones, 8 aldehydes, and 8 ethers were collected with a Fourier transform mass spectrometer equipped with a laser desorption ionization source. Selectivities of the metal ions for the three organic classes are quantitated and compared to 70-eV electron impact (EI) data. While a 100% recognition accuracy for the three classes is obtained for EI, Cu/sup +/, and Sc/sup +/ data, the fewest features are required for, and the best separation is produced with, the Sc/sup +/ data. The selected features are also examined for their chemical information, providing clues to the characteristic reactivities and reaction mechanisms for the metal ions with three functional groups.