Vibrational exciton coupling in pure and composite sulfur dioxide aerosols.

Icy aerosol particles determine weather processes in planetary atmospheres and are discussed as sites of chemical reactions in interstellar dust. One of the interesting ice systems in this context are pure and composite SO2 particles. Vibrational exciton coupling is exploited in the present study to understand the properties of SO2 aerosol particles from their infrared spectroscopic signatures.

Unraveling the origin of band shapes in infrared spectra of N2O-12CO2 and 12CO2-13CO2 ice particles.

Band structures in the region of strong infrared absorption bands for different N2O-12CO2 and 12CO2-13CO2 composite particles are investigated by combining quantum mechanical exciton calculations with systematic experimental investigations. The ice particles are generated by collisional cooling and characterized with rapid-scan infrared spectroscopy. The size of the particles lies between approximately 10 and 100 nm.

Vibrational delocalization in ammonia aerosol particles.

The present contribution investigates shape effects and surface effects in the infrared spectra of pure (NH(3)) and mixed (NH(3)-CO(2) and NH(3)-NH(2)D-NHD(2)-ND(3)) ammonia particles with sizes between about 1 and 50 nm. The particles investigated have been generated in a collisional cooling cell as aerosols at temperatures between 20 and 80 K. The contribution reveals that only the combination with a microscopic model leads to a comprehensive understanding of the various features observed in the experimental infrared spectra.