TY - JOUR

T1 - Amorphous and crystalline aerosol particles interacting with water vapor: conceptual framework and experimental evidence for restructuring, phase transitions and kinetic limitations.

AU - Mikhailov, E.

AU - Vlasenko, S.

AU - Martin, S. T.

AU - Koop, T.

AU - Pöschl, U.

PY - 2009/12/16

Y1 - 2009/12/16

N2 - Interactions with water are crucial for the properties, transformation and climate effects of atmospheric aerosols. Here we present a conceptual framework for the interaction of amorphous aerosol particles with water vapor, outlining characteristic features and differences in comparison to crystalline particles. We used a hygroscopicity tandem differential mobility analyzer (H-TDMA) to characterize the hydration and dehydration of crystalline ammonium sulfate, amorphous oxalic acid and amorphous levoglucosan particles (diameter ~100 nm, relative humidity 5–95% at 298 K). The experimental data and accompanying Köhler model calculations provide new insights into particle microstructure, surface adsorption, bulk absorption, phase transitions and hygroscopic growth. The results of these and related investigations lead to the following conclusions: (1) Many organic substances, including carboxylic acids, carbohydrates and proteins, tend to form amorphous rather than crystalline phases upon drying of aqueous solu

AB - Interactions with water are crucial for the properties, transformation and climate effects of atmospheric aerosols. Here we present a conceptual framework for the interaction of amorphous aerosol particles with water vapor, outlining characteristic features and differences in comparison to crystalline particles. We used a hygroscopicity tandem differential mobility analyzer (H-TDMA) to characterize the hydration and dehydration of crystalline ammonium sulfate, amorphous oxalic acid and amorphous levoglucosan particles (diameter ~100 nm, relative humidity 5–95% at 298 K). The experimental data and accompanying Köhler model calculations provide new insights into particle microstructure, surface adsorption, bulk absorption, phase transitions and hygroscopic growth. The results of these and related investigations lead to the following conclusions: (1) Many organic substances, including carboxylic acids, carbohydrates and proteins, tend to form amorphous rather than crystalline phases upon drying of aqueous solu

KW - atmospheric aerosols

KW - hygroscopic growth

KW - carboxylic acids

U2 - 10.5194/acp-9-9491-2009

DO - 10.5194/acp-9-9491-2009

M3 - Article

VL - 9

SP - 9491

EP - 9525

JO - Atmospheric Chemistry and Physics

JF - Atmospheric Chemistry and Physics

SN - 1680-7316

IS - 24

ER -