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Free Radical

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Certain molecules,when are torn apart, give up large amounts of energy upon recombining. In the 1950's it was proposed that such 'free radicals' could be used as rocket propellants. However free radicals recombine as soon as they are formed, and despite research over the decades no method has been found to keep them stable long enough to use as a propellant. Atomic hydrogen was the most promising of these free radicals, which might yield a specific impulse of over 1,100 seconds, three times that of conventional chemical propellants.

Free radicals could deliver the following performance (SH2=Solid H2 Free Radical)

  • 25%H/SH2 Free Radical. Specific impulse: 680 seconds. Temperature of Combustion: 2,050.00 K
  • 33%H/SH2 Free Radical. Specific impulse: 790 seconds. Temperature of Combustion: 2,600.00 K
  • 63%H/SH2 Free Radical. Specific impulse: 1,140 seconds. Temperature of Combustion: 4,500.00 K.
  • 100%He Free Radical. Specific impulse: 900 seconds.