From C4H7N2Ge0.4Sn0.6Br3 to C6H11N2Ge0.4Sn0.6Br3: Effective
Modulation of the Second Harmonic Generation Effect and Optical Band
Gap by Planar π‑Conjugated Organic Cation Size
posted on 2024-01-22, 06:05authored byYuwei Kang, Can Yang, Jie Gou, Yaolong Zhu, Qingwen Zhu, Qi Wu
In the search for nonlinear optical
(NLO) materials with
excellent
overall performance, we have devoted ourselves to organic–inorganic
hybrids consisting of anionic groups containing stereochemically active
lone-pair (SCALP) electron cations and organic planar π-conjugated
group cations. Accordingly, in this paper, two novel organic–inorganic
hybrid metal halides, C4H7N2Ge0.4Sn0.6Br3 (I) and C6H11N2Ge0.4Sn0.6Br3 (II), have been synthesized. The powder second-harmonic technique
shows that both C4H7N2Ge0.4Sn0.6Br3 and C6H11N2Ge0.4Sn0.6Br3 have moderately
strong second-order nonlinear optical effects, which are about 2.03
(I) and 1.16 (II) times that of KH2PO4 (KDP),
respectively. They also have different optical band gaps of 2.75 (I)
and 2.88 eV (II) due to the different sizes of the organic cations,
and their photoluminescent and thermal properties were also investigated.
This work provides new structural insights for the design and modulation
of organic–inorganic hybrid halide materials with multiple
excellent optical properties.