Spectrometry and Appearance Potentials

In Table XXI are listed those compounds which have been studied in some detail by the use of this technique. 

The normal fragmentation pattern for a compound RsSiM(CO)s involves loss of CO and concomitant loss of R (especially when R = H) although Si-M cleavage may occur, SiM is always an abundant species. For the compounds H2Si[M(CO)s]2 (M = Mn, Re entry 6), the following pattern has been established, where a = 0-2 and y = 0-10  

Other processes (all established by the observation of enhanced metastable peaks) include elimination of R-R, SiR2, and M(CO)j, e.g. (.32), 

The cationic product in Eq. (127) is a substituted silicenium ion attempts to produce a corresponding species chemically by abstraction of R from R3SiM(CO) or R2Si[M(CO) ]2 have all been unsuccessful [see Section III,C and Ref. (24) Thus addition of the chloride-ion acceptor SbCls to Cl iRe(CO) results in Si-Re bond cleavage (32). 

Mass Spectroscopic Studies of Silicon-Transition-Metal Compounds 

---