Enthalpy of formation of benzo[k]fluoranthene

The standard molar enthalpy of formation of benzo[k]fluoranthene, (CAS number 207-08-9) in the crystalline state, at T = 298.15 K, was determined as Delta(f)H(m)(o)(C20H12, cr) = (172.4 +/- 4.3) kJ.mol(-1), by micro-combustion calorimetry. Vapour pressure against temperature measurements recorded using the Knudsen effusion method led to Delta(cr)(g)H(m)(o)(C20H12) = (124.2 +/- 4.7) kJ.mol(-1), at T = 298.15 K and hence Delta(f)H(m)(o) (C20H12, g) = (296.6 +/- 6.4) kJ.mol(-1), at T = 298.15 K. The results reported in this work show that, in terms of the homodesmotic stabilization enthalpy criteria, benzo[k]fluoranthene is an aromatic compound, in agreement with the evidence from H-1-NMR spectroscopy, and the prediction by Craig's rules. (C) 2002 Elsevier Science Ltd. All rights reserved.