Ab initio molecular dynamics simulation of photoisomerization in azobenzene in the n{pi}* state

Journal Article · Sat Nov 21 00:00:00 EST 2009 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.3263918· OSTI ID:21559804

Ootani, Yusuke; Satoh, Kiminori; Nakayama, Akira; Noro, Takeshi ^[1]; Taketsugu, Tetsuya ^[1]

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1. Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo 060-0810 (Japan)

Photoisomerization mechanism of azobenzene in the lowest excited state S{sub 1}(n{pi}*) is investigated by ab initio molecular dynamics (AIMD) simulation with the RATTLE algorithm, based on the state-averaged complete active space self-consistent field method. AIMD simulations show that cis to trans isomerization occurs via two-step rotation mechanism, accompanying rotations of the central NN part and two phenyl rings, and this process can be classified into two types, namely, clockwise and counterclockwise rotation pathways. On the other hand, trans to cis isomerization occurs via conventional rotation pathway where two phenyl rings rotate around the NN bond. The quantum yields are calculated to be 0.45 and 0.28{+-}0.14 for cis to trans and trans to cis photoisomerizations, respectively, which are in very good agreement with the corresponding experimental results.

• OSTI ID: 21559804
• Journal Information: Journal of Chemical Physics, Vol. 131, Issue 19; Other Information: DOI: 10.1063/1.3263918; (c) 2009 American Institute of Physics; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ALGORITHMS
EXCITED STATES
ISOMERIZATION
MOLECULAR DYNAMICS METHOD
PHOTOCHEMISTRY
ROTATION
SELF-CONSISTENT FIELD
SIMULATION
CALCULATION METHODS
CHEMICAL REACTIONS
CHEMISTRY
ENERGY LEVELS
MATHEMATICAL LOGIC
MOTION