The Vapor Pressures and Enthalpies of Sublimation of Five Polycyclic Aromatic Hydrocarbons

Abstract

The vapor pressures over benz[a]anthracene (B[a]A), benzo[a]pyrene (B[a]P), benzo[e]pyrene (B[e]P), benzo[ghi]perylene (B[ghi]P), and coronene have been measured using the Knudsen effusion weight loss method. The parameters A and B in the equation log 10 [p(atm)] = -(A/T) + B and the enthalpies of sublimation in kcal mol −1 derived therefrom are respectively: B[a]A, 5925 ± 36, 10.045 ± 0.099, 27.12 ± 0.54; B[a]P, 6181 ± 32, 9.601 ± 0.083, 28.29 ± 0.51; B[e]P, 6220 ± 33, 9.736 ± 0.085, 28.46 ± 0.55; B[ghi]P, 6674 ± 40, 9.519 ± 0.093, 30.54 ± 0.55; coronene, 7100 ± 69, 9.110 ± 0.149, 32.49 ± 0.55. The errors shown for the A and B values are standard deviations and for the enthalpies of sublimation are estimates of total probable error.