As shown in figure 2, this creates a conjugated system
via the two aromatic rings, known as a quinone imide.
This is due to the much larger molecule number density in the solid film than that in the solution, especially to the much larger delocalized [pi]-electrons conjugated system
formed in the film.
The effect of extending the conjugated system
by means of fusing a large aromatic structure to the 4- and 5- positions of the oxazole ring has not been considered.
X-ray analysis reveals that the atoms of C(1) to C(8), N(1) and N(2) form a planar and N2, C3, C2, C1 and N1 atoms can form a conjugated system
Porphyrins are conjugated systems
because they contain alternating single and double bonds.
Although he continues his interest in unusual conjugated systems
, his major emphasis in recent years has been on the synthesis and study of molecules that imitate enzymatic reactions.
Topics include optical microscopy and spectroscopy of single molecules, optical properties of single conjugated polymer chains (polydiacetylenes), morphology-correlated photophysics in organic semiconductor thin films by confocal laser microscopy and spectroscopy, spectroscopy of long-lived photoexcitations in pi- conjugated systems
, charge transport in disordered organic semiconductors, probing organic semiconductors with terahertz pulses, macroscopic polarization and exciton properties for strong exciton polaritons in anisotropic crystals, sub-5 fs spectroscopy of polydiacetylene, and ultrafast optoelectronic probing of excited states in low-dimensional carbon-based pi-conjugated materials.