No, hexagonal diamond is not graphite not at all!
Graphite has sp2 hybrid bonds.
Diamond (either cubic or hexagonal) has sp3 hybrid bonds; tetrahedral bonds in cubic and hexagonal diamond - but a different crystal structure.
Poly(hydridocarbyne) (PHC) polymer thermolizes (decomposes) under heat and inert atmosphere to diamond. It doesn't char to sp3 carbon (graphite), it simply looses the single hydrido substituent (hydrogen) and the suddenly "free" fourth sp3 bond is ready to party... but since the only "people" at the "party" are just more decomposing PHC molecules, they have no choice but to "hook-up" with another carbon in sp3 bond. Viola! Diamond. Or rather, diamond-like-carbon (DLC) first, then as the temperature increases toward 600 C hexagonal diamond.
I cringe to mention this - but give google a spin on "hexagonal diamond".
Cheers.
klick et al - hey, there's already an alternative to this (and CVD diamond) - it's a new polymer called 'poly(hydridocarbyne)'.
Upon heating to 100 C to 800 C in an argon atmosphere it decomposes
into hexagonal diamond (a tad different from the more common cubic diamond). See http://en.wikipedia.org/wiki/Poly(hydridocarbyne).
I can imagine quite a few things I'd make from it - like... uh... diamond fiber for Space Elevators (cough).
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No, hexagonal diamond is not graphite not at all! Graphite has sp2 hybrid bonds. Diamond (either cubic or hexagonal) has sp3 hybrid bonds; tetrahedral bonds in cubic and hexagonal diamond - but a different crystal structure. Poly(hydridocarbyne) (PHC) polymer thermolizes (decomposes) under heat and inert atmosphere to diamond. It doesn't char to sp3 carbon (graphite), it simply looses the single hydrido substituent (hydrogen) and the suddenly "free" fourth sp3 bond is ready to party ... but since the only "people" at the "party" are just more decomposing PHC molecules, they have no choice but to "hook-up" with another carbon in sp3 bond. Viola! Diamond. Or rather, diamond-like-carbon (DLC) first, then as the temperature increases toward 600 C hexagonal diamond.
I cringe to mention this - but give google a spin on "hexagonal diamond".
Cheers.
klick et al - hey, there's already an alternative to this (and CVD diamond) - it's a new polymer called 'poly(hydridocarbyne)'. Upon heating to 100 C to 800 C in an argon atmosphere it decomposes into hexagonal diamond (a tad different from the more common cubic diamond). See http://en.wikipedia.org/wiki/Poly(hydridocarbyne).
I can imagine quite a few things I'd make from it - like ... uh ... diamond fiber for Space Elevators (cough).