Photostability and solvation: photodynamics of microsolvated zwitterionic glycine

0355636 - ÚFCH JH 2011 RIV GB eng J - Journal Article
Ončák, Milan - Lischka, Hans - Slavíček, Petr
Photostability and solvation: photodynamics of microsolvated zwitterionic glycine.
Physical Chemistry Chemical Physics. Roč. 12, č. 19 (2010), s. 4906-4914. ISSN 1463-9076. E-ISSN 1463-9084
R&D Projects: GA ČR GA203/09/0422; GA MŠMT LC512
Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z40550506
Keywords : zwitterionic glycine * photodynamics * photostability
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 3.454, year: 2010

Photoinduced processes of the zwitterionic glycine solvated with one and two water molecules were investigated using both static (CASSCF, MRCI and EOM-CCSD methods) and excited state non-adiabatic molecular dynamics (full multiple spawning method) approaches. Reaction pathways were identified and the respective yields and timescales determined. Excitation to the two lowest states, corresponding to the onset of the glycine absorption spectrum, was considered and the conformational dependence of the photochemical behavior was explored. The main processes on the femtosecond timescale are C-N dissociation producing the ammonia molecule, dissociation of hydrogen atom from the amino group and regeneration of the non-ionized glycine molecule via hydrogen transfer. It is found that the photochemical reaction yields strongly depend on the cluster conformation. A significant fraction of the electronic population is trapped in the n pi* minimum and the system deactivates on longer timescales.
Permanent Link: http://hdl.handle.net/11104/0194358