the extreme values at the aromatic ring regions are significantly
different, which would cause different strength of noncovalent
interaction and solid morphology [36]. In addition, the
complexation energies of dimers of bioxazole isomers in gas
phase were also calculated to estimate the strength of noncovalent
intermolecular interactions with functional and basis set of M06-
strong interaction of C5-C5'_BOxz suggest its potential
applications for OFET devices. This work provides a valuable
strategy for synthesizing C2(5)-C2ʹ(5ʹ) linked bioxazole
isomers as well as investigating the orientation effects on their
optical properties and further applications.
2
(
X-D3/6-311+G(d,p) [37]. The basis set superposition error
BSSE) corrected complexation energies of C2-C2'_BOxz, C2-
C5'_BOxz and C5-C5'_BOxz antiparallel displaced dimers are -
9.84, -21.68 and -21.81 kcal/mol, respectively. This increasing
Declaration of interests
1
The authors declare that they have no known
competing financial interests or personal
relationships that could have appeared to influence
the work reported in this paper.
trend (absolute value) of complexation energies of bioxazole
dimers indicated the increasing strength of intermolecular
interaction (π-π stacking interaction, shown in Fig. 2) [38], and
might be the reason for the red-shifts in the photoluminescence
spectra of bioxazole isomers in film state. Similar results, stronger
intermolecular interaction of 5,5'-biazoles than that of 2,2'-
biazoles, can also be observed at other literature and would be
beneficial for high-performance OFET [8].
Acknowledgments
We gratefully thank the financial support from the National
Natural Science Foundation of China (Nos. 21801028, 11704050,
6
1505015), Scientific Research Project of the Department of
Education of Sichuan Province (Nos. 2018Z099) and Project of
Sichuan Provincial Science and Technology Department (Nos.
2
017FZ0085). We would like to thank Dr. Danyang Wan for the
quantum chemical calculations in this paper.
Fig. 2. Gradient isosurfaces (s = 0.5 au) for antiparallel displaced
dimer of a) 2,5-Oxz, b) C2-C2'_BOxz, c) C2-C5'_BOxz and d) C5-
C5'_BOxz. ΔE means BSSE corrected complexation energies of
dimers; the color-mapped reduced density gradient (RDG) isosurface
between dimer means π-π interaction.
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8
-1
r
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