The synthesis and single-crystal X-ray structures of two quinacridone derivatives, N,N'-di(n-butyl)quinacridone (1) and N,N'-di(n-butyl)-1,3,8,10-tetramethylquinacridone (2), are reported, and the 1H NMR, absorption, photoluminescent (PL), and electroluminescent (EL) characteristics are presented. Both these crystal structures are characterized by intermolecular pi...pi and hydrogen bonding interactions. The intermolecular pi...pi interactions lead to the formation of molecular columns in the solids of 1 and 2, and the interplanar contact distances between two adjacent molecules are 3.48 and 3.55 angstroms, respectively. Crystals of 1 display shorter intermolecular pi...pi contacts and higher density than 2. These results suggest that tighter intermolecular interactions exist in 1. The 1H NMR, absorption, and PL spectra of 1 and 2 in solutions exhibit concentration-dependent properties. The PL quantum yields of 1 in solutions decrease more quickly with the increase of concentration compared to that of 2 in solutions. For solid thin films of Alq3:1 (Alq3 = tris(8-hydroxyquinolinato)aluminum), emission intensities dramatically decrease and obvious red shifts are observed when the dopant concentration is above 4.2%, while for films of Alq3:2, a similar phenomenon occurs when the concentration is above 6.7%. EL devices with Alq3:1 as emitting layer only show high efficiencies (20.3-14.5 cd/A) within the narrow dopant concentration range of 0.5-1.0%. In contrast, high efficiencies (21.5-12.0 cd/A) are achieved for a wider dopant concentration range of 0.5-5.0% when Alq3:2 films are employed as emitting layer. The different PL and EL concentration-dependent properties of the solid thin films Alq3:1 and Alq3:2 are attributed to their different molecular packing characteristics in the solid state.

Constitutional dynamic libraries of hydrazones (a)A(b)B and acylhydrazones (a)A(c)C undergo reorganization and adaptation in response to a chemical effector (metal cations) or a physical stimulus (light). The set of hydrazones [(1)A(1)B, (1)A(2)B, (2)A(1)B, (2)A(2)B] undergoes metalloselection on addition of zinc cations which drive the amplification of Zn((1)A(2)B)2 by selection of the fittest component (1)A(2)B. The set of acylhydrazones [E-(1)A(1)C, (1)A(2)C, (2)A(1)C, (2)A(2)C] undergoes photoselection by irradiation of the system, which causes photoisomerization of E-(1)A(1)C into Z-(1)A(1)C with amplification of the latter. The set of acyl hydrazones [E-(1)A(1)C, (1)A(3)C, (2)A(1)C, (2)A(3)C] undergoes a dual adaptation via component exchange and selection in response to two orthogonal external agents: a chemical effector, metal cations, and a physical stimulus, light irradiation. Metalloselection takes place on addition of zinc cations which drive the amplification of Zn((1)A(3)C)2 by selection of the fittest constituent (1)A(3)C. Photoselection is obtained on irradiation of the acylhydrazones that leads to photoisomerization from E-(1)A(1)C to Z-(1)A(1)C configuration with amplification of the latter. These changes may be represented by square constitutional dynamic networks that display up-regulation of the pairs of agonists ((1)A(2)B, (2)A(1)B), (Z-(1)A(1)C, (2)A(2)C), ((1)A(3)C, (2)A(1)C), (Z-(1)A(1)C, (2)A(3)C) and the simultaneous down-regulation of the pairs of antagonists ((1)A(1)B, (2)A(2)B), ((1)A(2)C, (2)A(1)C), (E-(1)A(1)C, (2)A(3)C), ((1)A(3)C, (2)A(1)C). The orthogonal dual adaptation undergone by the set of acylhydrazones amounts to a network switching process.

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A multi-color tunable circularly polarized luminescence (CPL) xerogel film with a large luminescence dissymmetry factor (glum) is achieved using a single compound upon protonation.

A polystyrene-block-poly(1,2-butadiene)-block-poly(tert-butyl methacrylate) (SBT) triblock copolymer and its analogues with different degrees of saponification, SB(T/A) with A being poly(methacrylic acid) are characterized in terms of their morphologies and infrared spectroscopic features. The chemical modification of the third block leads to a change of the overall morphology from a gyroid to a lamellar structure. Blends of these SB(T/A) triblock copolymers with polystyrene-block-poly(2-vinylpyridine) (SV) diblock copolymer and poly(2-vinylpyridine)-block-poly(cyclohexyl methacrylate) (VC) diblock copolymer were prepared and characterized. Attractive segmental interactions through hydrogen bonds between A and V blocks have been monitored by infrared spectroscopy. Upon increasing the amount of proton donors, the amount of hydrogen bonds between A and V units also increased. Superlattices composed of the two block copolymers were obtained by casting films from a mixed solution of these block copolymers in tetrahydrofuran (THF) and were investigated by transmission electron microscopy (TEM). Varying the amount of hydrogen-bonding donors via controlled saponification of the SBT triblock copolymer lead to different superlattices in blends with SV and VC diblock copolymers.

The synthesis of two alkyl substituted quinacridone derivatives, N,N'-di(n-hexyl)-1,3,8,10-tetramethylquinacridone (1) and N,N'-di(n-hexyl)-2,9-di(t-butyl)quinacridone (2), and four dendritic quinacridone derivatives, N,N'-didendritic-1,3,8,10-tetramethylquinacridones (3-G1 and 3-G2) and N,N'-didendritic-2,9-di(tert-butyl)quinacridones (4-G1 and 4-G2) are reported. X-ray crystal structure and thermal analysis revealed that the quinacridone derivatives reported in this paper exhibit the evolution from crystalline phase to amorphous phase upon varying from alkyl substituted quinacridones to dendritic quinacridones. The concentration-dependent 1H NMR, UV-vis, and photoluminescence (PL) spectroscopic studies demonstrated the aggregation properties of the quinacridone derivatives in solution. For dendritic quinacridones with the sufficient shield of dendrons, the fluorescence concentration quenching can be significantly suppressed and emission intensity in concentrated solution and solid state could be greatly enhanced. Compound 4-G2 displays good solution process property and higher PL yield in concentrated solution, suggesting that it is a potential candidate for the fabrication of high-performance organic electroluminescent devices (OLEDs) on the basis of low-cost solution process technique.

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The salicylidene Schiff base N-3,5-dichloro-salicylidene-(S)-alpha-phenylethylamine (SPEA) has been synthesized and characterized. Stimulated by one optical input (UV light) and two chemical inputs (OH(-) and Zn(2+)), SPEA undergoes reactions of photochemistry, deprotonation, and complexation. Tailing these reactions by means of the UV-vis absorption spectra and fluorescence spectra, two obvious optical outputs, an absorption band at 323 nm and a fluorescent emission peak at 460 nm, have been obtained. On the basis of encoding binary digits in these inputs and outputs applying positive logic conventions, one monomolecular circuit, which integrates one OR, two NOT, and four AND gates, has been achieved.