Articles | Volume 14, issue 7
Atmos. Chem. Phys., 14, 3691–3701, 2014
Atmos. Chem. Phys., 14, 3691–3701, 2014

Research article 10 Apr 2014

Research article | 10 Apr 2014

Oligomer formation within secondary organic aerosols: equilibrium and dynamic considerations

E. R. Trump and N. M Donahue E. R. Trump and N. M Donahue
  • Carnegie Mellon University, Center for Atmospheric Particle Studies, 1106 Doherty Hall, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA

Abstract. We present a model based on the volatility basis set to consider the potential influence of oligomer content on volatility driven secondary organic aerosol (SOA) yields. The implications for aerosol evaporation studies, including dilution, chamber thermo-equilibration, and thermodenuder studies, are also considered. A simplified description of oligomer formation reproduces essentially all of the broad classes of equilibrium and dynamical observations related to SOA formation and evaporation: significant oligomer content may be consistent with mass yields that increase with organic aerosol mass concentration; reversible oligomerization can explain the hysteresis between the rate of SOA formation and its evaporation rate upon dilution; and the model is consistent with both chamber thermo-equilibration studies and thermodenuder studies of SOA evaporation.

Final-revised paper