Photodissociation of silicon carbide cluster cations

Small clusters of silicon carbide ( Si x C y + , x = 3 – 10 , y = 1 – 2 ) are produced by laser vaporization in a pulsed molecular beam and detected with time-of-flight mass spectrometry. Specific clusters are mass selected and photodissociated at 355 nm. Si3C+ is an especially abundant cluster in the mass spectrum, and it is produced often as a fragment from larger clusters, suggesting that it is relatively more stable than other small cations. The smaller clusters (Si3–5C+) fragment primarily by the loss of neutral Si atoms, while larger clusters (Si7–10C+) lose neutral Si2C and Si3C, which are concluded to be more stable neutrals.