TY  - JOUR
A1  - Luo, Ying
A1  - Utecht, Manuel Martin
A1  - Dokic, Jadranka
A1  - Korchak, Sergey
A1  - Vieth, Hans-Martin
A1  - Haag, Rainer
A1  - Saalfrank, Peter
T1  - Cis-trans isomerisation of substituted aromatic imines a comparative experimental and theoretical study
T2  - ChemPhysChem : a European journal of chemical physics and physical chemistry
N2  - The cis-trans isomerisation of N-benzylideneaniline (NBA) and derivatives containing a central C=N bond has been investigated experimentally and theoretically. Eight different NBA molecules in three different solvents were irradiated to enforce a photochemical trans (hv) -> cis isomerisation and the kinetics of the thermal backreaction cis (Delta)-> trans were determined by NMR spectroscopy measurements in the temperature range between 193 and 288 K. Theoretical calculations using density functional theory and Eyring transition-state theory were carried out for 12 different NBA species in the gas phase and three different solvents to compute thermal isomerisation rates of the thermal back reaction. While the computed absolute rates are too large, they reveal and explain experimental trends. Time-dependent density functional theory provides optical spectra for vertical transitions and excitation energy differences between trans and cis forms. Together with isomerisation rates, the latter can be used to identify "optimal switches" with good photochromicity and reasonable thermal stability.
KW  - density functional calculations
KW  - imines
KW  - isomerization
KW  - photochemistry
KW  - thermochemistry
Y1  - 2011
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/36677
SN  - 1439-4235
VL  - 12
IS  - 12
SP  - 2311
EP  - 2321
PB  - Wiley-VCH
CY  - Weinheim
ER  -