ENTHALPIES OF FORMATION OF FREE RADICALS – REACTION INTERMEDIATES IN LIGNIN PYROLYSIS | Journal ...

It is shown that the enthalpies of production for a variety of carbon and oxygen centred aromatic free radicals connected to lignin may be simply determined mathematically. The calculations are based on the assumption that the enthalpy of formation for a given radical can be calculated from the experimental value for an appropriate unsubstituted free radical while accounting for I the contribution in enthalpy of formation caused by the substituent and ii) the correction term that reflects an electronic effect of the substituent. The latter can be estimated using the relative free radical stability data.

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