Steered molecular dynamics and free energy calculations of pahs condensation on soot surface

The nonbond interactions of PAHs and soot are studied quantitatively by calculating the free energy profiles of condensation on fullerenes surface through steered molecular dynamics (SMD). PAH condensation simulations suggest that PAH condensation should not be ignored in soot mass growth. For large fullerenes (diameter ~1.8 nm), most PAH can condense on the surfaces at flame temperatures. Two condensation modes were discovered in our simulations, namely the H shape and the V shape. For fullerene with a diameter no less than 1.8nm (C540), even A4 can condensed at a flame temperature (~1500K), and the A10 can condensed on fullerene surface stable even at 2000K.