Gas-phase clustering reactions of SiH3+ with SiH4 and H-2 were studied
using a pulsed-electron beam mass spectrometer. The bond dissociation
energy of SiH3+... SiH4 was estimated to be greater than or equal to
35 kcal/mol and those of SiH3+ (H-2)(n) with n = 1 and 2 were measured
to be 14.2 and 4.8 kcal/mol in good agreement with the theoretical va
lues. The clusters are found to have the shell structures, SiH3+(sol)2
(sol)n-2 for both sol = SiH4 and H-2.