Struct Chem
conditions. The structures of the complexes were determined
by single-crystal X-ray diffractions. The four complexes are
further constructed into 3D supramolecular structures via dif-
ferent intermolecular hydrogen bonds and interesting π–π
stacking interactions. Moreover, Hirshfeld surface analysis
was used to further study the intermolecular interactions of
the synthesized complexes; the results agree well with their
single-crystal structure analyses. The packing structure of
complex 4 is different to the other three complexes, which is
just effected by the position of carboxylate group of the li-
gand. Thermal behavior investigations indicate that the struc-
tures of complexes 3 and 4 possess good thermal stabilities,
with obvious exothermic phenomena in the decomposition
processes. Besides, complex 1 shows a strong emission band
at 356 nm when excited at 290 nm. Further studies based on
triazole-carboxylate ligands are under way in our laboratory.
Fig. 12 TGA curves of complexes 3 and 4 measured in nitrogen
atmosphere at a heating rate of 10 °C min−
1
3
, the first step takes place in the range of 130–200 °C with a
Funding This work was supported by the National Natural Science
Foundation of China (grant numbers 21371151, 21461029, and
weight loss of 14.4%, corresponding to the release of four
coordinated water (calcd. 14.2%). Then, a rapid and signifi-
cant weight loss of 26.3% is observed in the range of 340–
2
1561033).
Compliance with ethical standards
4
40 °C, which could be assigned to the decomposition of
−
triazole group of 3-Htba ligands (calcd. 26.8%). Further
heating leads to more weight loss, which corresponds to the
continue decomposition of the remaining skeleton. In the case
of complex 4, the TGA curve shows a 14.2% weight loss at
about 114–227 °C, corresponding to the loss of four water
molecules (calcd. 14.2%). Similarly, a rapid weight loss of
Conflict of interest The authors declare that they have no conflict of
interest.
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Conclusion
In summary, four new transition metal complexes based on
3
1
-(1H-1,2,4-triazol-1-yl)benzoic acid and 4-(1H-1,2,4-triazol-
-yl)benzoic acid have been synthesized under solvothermal
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