K3C6N7O3·2H2O: A Multifunctional Nonlinear Optical Cyamelurate Crystal with Colossal π-Conjugated Orbitals

Xinyuan Zhang; Xiaoguang Du; Jinhui Wang; Fangyan Wang; Fei Liang; Zhanggui Hu; Zheshuai Lin; Yicheng Wu

doi:10.1021/acsami.2c15835

K₃C₆N₇O₃·2H₂O: A Multifunctional Nonlinear Optical Cyamelurate Crystal with Colossal π-Conjugated Orbitals

ACS Appl Mater Interfaces. 2022 Nov 30;14(47):53074-53080. doi: 10.1021/acsami.2c15835. Epub 2022 Nov 15.

Authors

Xinyuan Zhang¹, Xiaoguang Du¹, Jinhui Wang¹, Fangyan Wang², Fei Liang², Zhanggui Hu¹, Zheshuai Lin³, Yicheng Wu^{1

2}

Affiliations

¹ Tianjin Key Laboratory of Functional Crystal Materials, Institute of Functional Crystals, Tianjin University of Technology, Tianjin 300384, China.
² State Key Laboratory of Crystal Materials and Institute of Crystal Materials, Shandong University, Jinan 250100, China.
³ Functional Crystals Lab, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China.

PMID: 36379003
DOI: 10.1021/acsami.2c15835

Abstract

The delocalized π-conjugated units are considered as an advantageous gene for improving the optical nonlinearity of acentric crystals. For the first time, we synthesized a new acentric SHG-active metal cyamelurate crystal K₃C₆N₇O₃·2H₂O (I) by a facile solution method, containing a colossal planar π-conjugated (C₆N₇O₃)^3- unit. It displays a strong second-order harmonic generation (SHG) of 4 × KDP and a giant anisotropic birefringence of 0.446 at 1064 nm. The theoretical calculations reveal that such substantial improvement is contributed from the strong molecular susceptibility of (C₆N₇O₃)^3- units and their near-perfect coplanar arrangement. Moreover, I exhibits a broadband ultraviolet photoluminescence at 366 nm, suggesting its multifunctional capacity and great potential for compact highly integrated optoelectronic devices.

Keywords: cyamelurate; noncentrosymmetric; nonlinear optical crystal; second harmonic generation; π-conjugated structure.