โ Scribed by Ciping Shen; Steven G. Mayorga; Richard Biagioni; Charles Piskoti; Masahiro Ishigami; Alexander Zettl; Neil Bartlett
No coin nor oath required. For personal study only.
Hexagonal boron nitride, h-BN, is intercalated, at &203C, by S 2 O 6 F 2 (the source of the powerfully oxidizing SO 3 F z radical) to give a deep blue solid (BN) &3 SO 3 F, which is a temperatureindependent paramagnet (x g +55.2ุ10 ุ 6 cgs units). Four probe conductivity measurements on an intercalated piece of highly oriented pyrolytic BN (HOPBN) have established an approximate doubling of the conductivity with temperature decrease from 295 to 77 K. The low conductivity ( 295K โซุโฌ 1.5 S cm ุ 1 ) is attributed to high e4ective carrier mass deriving from poor p N +p overlap and consequent narrow band character. The conductivity at 295 K of a graphite relative of composition C &8.5 SO 3 F made from a HOPG chip was found to be 1.1;10 5 S cm ุ 1 , and at 77 K it was found to be 3.1;10 5 S cm ุ 1 . Other blue, poorly conductive h-BN intercalation compounds have been obtained using SbF 5 /F 2 mixtures on h-BN, and from AsF 5 on (BN) &3 SO 3 F, but they are of unknown composition.
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