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Updated: Jul 30, 2025
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Cs2Mg(H2C3N3S3)4·8H2O: An Excellent Birefringent Material with Giant Optical Anisotropy in π-Conjugated
Xia Hao1, Chensheng Lin2, Min Luo2
1School of Materials Science and Engineering, Henan Normal University, Xinxiang 453007, P. R. China.
Abstract:
The design of giant birefringence was performed by adjusting cations to make parallel and compact alignments of π-conjugated (HC3N3S3), where x = 1 and 2) groups with large polarizability anisotropy. Finally, the first mixed alkali/alkali-earth-metal trithiocyanurates, A2B(H2C3N3S3)4·nH2O (A = K, Rb, Cs; B = Mg, Sr; n = 5-8, 12), were designed and synthesized successfully. Importantly, Cs2Mg(H2C3N3S3)4·8H2O (III) and K2Sr(H2C3N3S3)4·5H2O (IV) possess large birefringences of 0.580 and 0.194 at 800 nm, respectively, of III has the largest birefringence among all practical birefringent crystals, cyanurates, and hydroisocyanurates.
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