Positive and negative ion sublimation from transition metal surfaces: A review of some recent results

Singly cha rged , positive and negative, atomi c ions ha ve been observed to s ublime freely from 4d and 5d tran siti on metal surfaces in th e 1800 to 2600 K tempe rature ran ge. Th e rates of sublim atio n we re found to be about equal to those which would be observed und er co ndition s of th ermal eq uilibrium. Ion sublimati on energies were obt ained fro m the te mperature depe ndence of th ese subli ma ti on rates. The energies were found to be consistent with currently a ccepted value s for th e atom su blimation ene rgy, electron work fun c tion, and first ion ization potentials of the elements investigated.