Aerosols
Last modified by jhtniska@helsinki_fi on 2024/02/07 06:22
Aim: Characterize and predict signatures of clustering of sulphur acid, water, amines etc.
Notes from the KCCP seminar 28.9.2012 by Ville Loukonen (H2SO4+ammonia, H2SO3+dimethylamine clusters)
- Strong correlation between aerosol formation and sulphuric acid content
- Electronic energy + harmonic vibr.analysis -> partition function -> any thermodynamics quantity, in particular entropy -> Gibbs free energy
- CP2K calculations: RT, NVT, 0.5 fs step, PBE, TZV2P, 600 Ry, 20x20x20 Å simulation cell, optim.geometries as starting config.
- T creates rotation but does not break bonds. No back-transfer of protons. HB switching time ~10-40 ps
- How to take collisions into account? E.g. NVE+ explicit carrier gas molecules
- Important paper: Ortega et al., Atm.Chem.Phys. 12, 225 (2012)
X-ray studies of aerosols
- Microscopic characterization of carbonaceous aerosol particle aging in the outflow from Mexico City, Atmos. Chem. Phys., 10, 961--976, 2010
- Chemistry for Sustainable Development 10, 603 (2002)
- Diffraction and absorption
- Aerosol analysis by soft X-ray spectromicroscopy near carbon absorption edge
- Spectrochimica Acta Part B 63 (2008) 1489--1495
Some preliminary calculations
- Basis set and functional dependence with ERKALE:
- The corresponding spectra from CP2K code:
- Comparison of the previous:
Some preliminary calculations
