The photodynamics of 2,4-diaminopyrimidine in comparison with 4-aminopyrimidine: The effect of amino-substitution

0351537 - ÚOCHB 2011 RIV NL eng J - Journal Article
Nachtigallová, Dana - Barbatti, M. - Szymczak, J. J. - Hobza, Pavel - Lischka, Hans
The photodynamics of 2,4-diaminopyrimidine in comparison with 4-aminopyrimidine: The effect of amino-substitution.
Chemical Physics Letters. Roč. 497, 1/3 (2010), s. 129-134. ISSN 0009-2614. E-ISSN 1873-4448
R&D Projects: GA MŠMT LC512
Institutional research plan: CEZ:AV0Z40550506
Keywords : nonadiabatic dynamical simulation * pyrimidine bases * ab initio methods
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 2.282, year: 2010

Nonadiabatic photodynamical surface hopping simulations of 4-aminopyrimidine and 2,4-diaminopyrimidine were performed at multi-configurational level. Additional NH2 substitution blocks part of the ring puckering modes necessary to reach ultrafast deactivation channels but does not affect the excited-state lifetime of 2,4-diaminopyrimidine significantly since other pathways leading to ultrafast relaxation can be utilized. The effect of the excess energy on the relaxation mechanism of 2,4-diaminopyrimidine was studied. It is shown that the amount of initial energy influences the time to reach the crossing seam and thus the lifetime. This study is important when interpreting the experimental results performed at different pump energies.
Permanent Link: http://hdl.handle.net/11104/0006168