Metal cluster compounds mass spectra

Example ED from untreated wire emitters in the presence of intentionally added alkali metal salts was used to obtain mass spectra of tartaric acid, arginine, pentobarbital and other compounds. [78,80] Besides [Mh-H]" quasimolecular ions, m/z 175, the FD mass spectrum of arginine exhibits [M+Na], m/z 197, and [Mh-K]", m/z 213, ions due to alkali metal cationization as well as [2M-i-H], m/z 349, cluster ions (Fig. 8.14). [37]... 

Elements with distinctive isotope ratios (Cl, Br, and transition metals, for example) will provide a distinctive isotopic cluster in the mass spectrum of a compound. This can be used to identify the presence of elements within unknown compounds. 

Endohedral metal fullerenes can be detected in relatively small amounts in the mass spectra in the laser vaporization cluster beams (vide supra). However, macroscopic quantities of these compounds may be produced rather readily either by vaporization in a laser furnace apparatus or by arc-burning of a composite rod of graphite and the corresponding metal oxide. In Fig. 4.50, a mass spectrum which illustrates the formation of a series of fullerene endohedral yttrium complexes obtained by laser vaporization of a composite graphite/ Y2O3 rod at 1200 ""C is reproduced. Among these species there is also one, Y2 Cs2, which corresponds to the inclusion of a metal cluster in the fullerene ball. 

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