4. CONCLUSIONS
To find new high-performance deep-UV NLO molecules, the superalkalis
(OLi3, ONa3, and OK3)
and graphynes (GY/GDY/GTY) were combined to design superalkali salts of
graphynes with considerable nonlinear optical (NLO) properties. Besides,
the dependence of first hyperpolarizability of the resulting compounds
on superalkali atom and pore size of graphyne were explored. The
superalkali-doped complexes have high structural stability, which can be
reflected by large interaction energies between the superalkali and
graphyne units, ranging from –34.97 to –61.15 kcal
mol-1. The atomic charge and frontier molecular
orbital studies reveal that these superalkali-doped complexes are
superalkali salts of graphynes. The superalkali and (pore) size of the
graphyne unit play extremely important roles in enhancingβ 0 values of the doped complexes. Based on the
best match between size of superalkalis and pore size of graphynes,
OLi3+@GTY– exhibits
the β 0 value (653420 au) of new record for
atom/superatom doped graphynes. Besides, these molecules have a working
waveband in the deep-ultraviolet region. Hence, these superalkali salts
of graphynes are new deep-UV NLO molecules with large second order NLO
response.
ACKNOWLEDGEMENTS
This work was supported by National Natural Science Foundation of China
(21373131
and 21573089), Shanxi Province Science Foundation for Youths
(201801D221066), and the 1331 Engineering of Shanxi Province.