Absorption cross section at 3.39 μm of alkanes, aromatics and substituted hydrocarbons

The present study reports gas phase absorption cross sections at 3.39 μm of 21 liquid hydrocarbons. Measurements were performed in the temperature range 303–413 K using an infrared He–Ne laser. In addition to n-alkanes, a number of cyclo-alkane, aromatic, and substituted hydrocarbons were investigated. The results demonstrate that (i) the absorption cross sections are temperature independent in the studied range, and that (ii) the aromatic and substituted hydrocarbons exhibit much smaller cross sections than n-alkanes for an identical number of C–H bonds. A tentative empirical correlation has been developed and shown to accurately predicts the cross section.