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A novel D3T derivative, 5-amino-4-cyano-3H-1,2-dithiole-3-thione (compound 1) has been obtained in one-pot reaction. The crystal is orthorhombic, space group Pbca, with a = 10.3667(4) A, b = 10.8898(4) A, c = 11.4942(5) A, V = 1297.60(9) A3, and Z = 8. In the crystal, molecules are firstly self-assembled into a complex sheet parallel to the (0 0 1) plane containing centrosymmetric R 2 4 (16) and R 4 4 (24) rings, and then the interconnection of molecular sheets through S···S interactions forms a three-dimensional supramolecular assembly. The DFT calculations are performed for isolated molecule using the B3LYP/6-31+G(d,p) methods. The frontier orbital properties of compound 1 have been reported and discussed. Moreover, a detailed assignment of the fundamental vibrational modes is proposed on the basis of the calculated results.

The present work examines the relationship between the crystal structures and chiroptical properties of four chiral Yb(III) complexes with camphor-derivative β-diketone ligands by means of solid-state circular dichroism (CD) spectroscopy. For the seven-coordinate complexes, [Yb(H2O)(d-hfc)3] (I) and [Yb(H2O)(l-hfc)3] (II) (d/l-hfc− = 3-heptafluorobutyryl-(+)/(−)-camphorate), the Λ- and Δ-diastereomers coexist in their crystals and no apparent bisignate couplets are observed in their solid-state CD spectra. A theoretical study indicates that the ground-state energy difference between the two diastereomers I and II is only 0.913 kcal mol−1, which explains why they could coexist in a crystal environment with the ratio of 1:1. While, eight-coordinate complexes Δ-[Yb(TPPO)2(d-hfc)3]·CHCl3·3C6H12 (III) and Λ-[Yb(TPPO)2(l-hfc)3]·CHCl3·3C6H12 (IV) (TPPO = triphenylphosphine oxide) are enantiopure in the solid-state, and typically negative and positive exciton splitting patterns around 330 nm are observed in their solid-state CD spectra. The solid-state CD spectra of these four complexes are in accordance with their X-ray single-crystal analyses. Besides, their solution CD spectra show that no particular isomer predominates in solution.