Hydrogen-bonded liquid crystal

Coco, S., Espinet, E., Espinet, P. and Palape, I. (2007) Functional isocyanide metal complexes as building blocks for supramolecular materials hydrogen-bonded liquid crystals. Dalton Transactions, (30), 3267-3272. 

It is the author s view that a chapter such as this needs some sort of context and needs to be self-contained. From this point of view, it will begin with a general introduction to liquid crystals themselves and will then introduce hydrogen-bonded liquid crystals in order to provide some context. The introduction to liquid crystals will not be referenced or illustrated heavily, so those readers requiring more information are directed to reference [1]. 

The greatest amount of work we have carried out with alkoxystil-bazoles is in the field of liquid crystals indeed, this is where our interest in stilbazoles started. After a brief and rather general introduction to liquid crystals, we will consider various types of complex that form liquid-crystal mesophases when complexed to stilbazoles, emphasizing patterns of behavior without delving into the subtleties. A more detailed discussion of the silver systems may be found elsewhere 24). Finally, although this article appears in a series that concentrates on inorganic chemistry, we offer an overview of some of our work with stilbazoles in hydrogen-bonded liquid crystals. 

Kato T (2000) Hydrogen-Bonded Liquid Crystals - Molecular Self-Assembly for Dynamically Functional Materials. 96 95-146 Katz E, see Shipway AN (2001) 99 237-281 Kauffmann GB, see Jorgensen CK (1990) 73 227-254 Keijzers CP, see Willemse J (1976) 28 83-126 Kelly JM, see Moucheron C (1998) 92 163-216... 

Hydrogen-Bonded Liquid Crystals Molecular Self-Assembly for Dynamically Functional Materials... 

Paleos, C. M., Tsiourvas, D., Supramolecular hydrogen-bonded liquid crystals , Liquid Crystals 2001, 28, 1127-1161. 

Keywords Hydrogen bonding. Liquid crystal. Liquid crystal polymer. Self-assembly, Selforganization, Complex, Gel, Supramolecular chemistry... 

The dimers of benzoic and cinnamic acid were probably the first hydrogen-bonded liquid crystals [16], Since this report early in the 20th century, a wide variety of aromatic acid dimers such as 55 have provided information on the structure and properties of liquid crystals [125-127], A notable example is compound 56 which shows an optically isotropic smectic D phase [127],... 

Fig. 6.17 Various types of hydrogen-bonded liquid crystals, such as dimer, trimer, side-chain, and main-chain complex.

Fig. 6.18 Hydrogen-bonding liquid crystal by dimerization. The rigid heads become sufficiently long to be the mesogenic core when hydrogen-bonded.

Fig. 6.20 Phase diagram of dimer-forming hydrogen-bonded liquid crystal. The thin solid Une is the 1/N transition hne, the thick solid hne is the N/S, transition line, and the dotted line is the binodal. The hatched area is the metastable region. The dark gray area with U is the unstable region due to entropy difference between two different species of N structures. The light gray area with U is the unstable region due to mixing two different species of molecules. The open circle represents the critical solution point. Parameters are fixed at ha = "B = "a "b 0 = 30.0,...

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