Crystal dyeing hydrogen bonding

Attempts to examine the process of cellulose crystallization have frequently involved culturing Acetobacter in the presence of fluorescent brighteners, direct dyes, carboxy-methyl-cellulose, or other agents which compete for interchain hydrogen bond sites, thereby disrupting microfibril formation... 

The availability of the coherent proton tunneling and cooperative proton tunneling and transfer of four protons in hydrogen bonds of benzoic acids crystals (including dye doped) have been revealed by Trommsdorff and collaborators [12,13] by reading the electron spectra of the crystals. 

The large values reported for squaraines indicate that noncentrosymmetric crystals or films of these dyes should be capable of efficient second harmonic generation (SHG). A new class of chiral D -A-D squaraines 37-44 obtained by 1,2-substitution of squaric acid showed second harmonic generation intensities of up to 64 times that of urea (Table 3) in the powder form [124,125]. X-ray crystal analysis indicated that two hydrogen bonds between adjacent mol-... 

Dendrimers, p. 432 Drug Delivery, p. 484 Dye Inclusion Crystals, p. 497 Enzyme Mimics, p. 546 Glycoluvil-Based Hosts, p. 597 Hydrogen Bonding, p. 658 Hydrophobic Ejfects, p. 673... 

Fig. 9 Hydrogen bonding, (a) Benzamide crystal containing Nile red in the 102 growth sectors. [100] is vertical. View along [010]. (b) Proposed structure of Nile red on the (102) face of benramide consistent with the linear dichroism and energy of the solvatochromic dye. View this art in color at WWW. dekker. com.)...

Concepts in Crystal Engineering, p. 319 Crystal Engineering with Hydrogen Bonds, p. 357 Crystal Structure Prediction, p. 371 Cfystalline Microporous Silicas, p. 380 Dye Inclusion Crystals, p. 497 Hofmann-Type Clathrates, p. 645 Mineralomimetic Structures, p. 868 Molecular Squares, Boxes, and Cubes, p. 909 Organic Zeolites, p. 996 Soft/Smart Materials, p. 1302... 

The formation of hydrogen bonds between the carboxylic acid groups of the functionalized liquid crystal copolymers and the pyridine portion of the dopants leads to stable, none separating mixtures. In mixtures containing up to 30 % of the dopants no separation was observed. Induction of a nematic mesophase is observed in the case of a smectic polymer matrix doped with low molecular weight photochromic dyes. 

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