Paper introduces new heteroazulene derivative, 10-methoxy-6-methyl-6
H
-5,6,7-triazadibenzo[
f,h
]
naphtho[3,2,1-
cd
]azulene (MMTNA), including chemical aspects of its synthesis likewise optical
absorption and
fl
uorescence spectra measured in several organic solvents of different polarity. The
obtained experimental results are subjected to the quantum-chemical analysis based on DFT/TDDFT/PCM
calculations at the B3LYP/6-31
þ
G(d,p) level of theory. MMTNA demonstrates insigni
fi
cant sol-
vatochromism of both
fi
rst absorption and
fl
uorescence bands caused mainly by a weakly polar feature of
its ground and lowest excited states. Despite this the emission bands appears to be considerably red
shifted with respect to relevant
fi
rst absorption bands resulting thus to a substantial Stokes shift. Its
origin is dominated by the conformational relaxation in the excited state whereas the solvent relaxation
has practically no in
fl
uence on the emission spectra. Low sensitivity to the host environment makes
MMTNA dye perspective for a number of applications, particularly in those cases when a high stability of
the emission wavelength (color) is demanded.
keywords in English:
optical absorption spectra, polarizable continuum model (PCM), fluorescence spectra, solvatochromism, DFT and TDDFT calculations, annulated heteroazulene dyes
departmental parameterization:
45
affiliation:
Wydział Chemii : Zakład Chemii Fizycznej i Elektrochemii