Mystery Substance -> Organometallic octane booster

[cliff at esl.eng.ohio-state.edu]

> The compound is ferrocene, (dicyclopentadienyl iron), Fe(C5H5)2, or Fc for
> short. 
>

This is one of several octane boosters of that class.  They apparently work by
scavaging the hydoxol radicals which promote rapid flame front speed.  I
found that iron, nickel, chromium, magnesium organometallics had been tried in 
the 50s (?) while researching octane boosting in the school library.  All except
lead and magnesium caused to much wear.  The oxides are to hard.  I used
MMT (methylcyclopentadienyl manganese tricarbonyl) for several hundred thousand
miles and decided it too caused more wear than I liked.  Ethyl Corp. produces
MMT and in 1998 got some favorable court rulings    see:
	 http://www.ethyl.com/news/7-20-98.html

I don't know what has happened since then.  A problem with these octane boosters
is they don't worked with oxygenated fuels (MTBE, gasohol, etc).  They 
oxidize in the tank.