Optical chromonics

Nonlinear optical properties were also found in thienyl derivatives bearing a chromone moiety in the structure such as 379 (99AM452 02CL984). 

Ruslim C, Hashimoto M, Matsunaga D, Tamaki T, Ichimura K. 2004. Optical and surface morphological properties of polarizing films fabricated from a chromonic dye by the photoalignment technique. Langmuir 20 95 100. 

A general correspondence between the optical textures, the X-ray diffraction patterns, and the forms of the phase diagrams has been observed for chromonic drugs and many dye/water systems [4-7]. The only significant difference between these two families of mesogens appears to be in some optical textures and rheological properties... 

As is usually found for mesophase systems, the boundaries on the phase diagram are not all equally easy to detect. All of the known chromonic mesophases are birefrin-gent and the clearing points can therefore be readily seen by optical microscopy. The crystalline solid-M phase boundary is often harder to detect optically, but it does show up readily in X-ray difiraction studies. Note also that some early chromonic phase diagrams determined by NMR did not show... 

In optical examinations of chromonic systems, the textures of both the one-phase and the two-phase regions tend to be highly characteristic [46]. The N phase usually... 

Note that the term herringbone is used in two different contexts in chromonic systems at the molecular level, to describe the transverse arrangement of columns in the M phase, and on a much larger scale, to describe the diagonally striped optical texture of the M phase grown by concentration of the N. 

Concerning the term chromonic, this word was coined to replace phrases such as lyotropic mesophases of the types formed by soluble aromatic mesogens . It was intended to echo the bis-chromone structure of DSCG and to carry connotations of dyes and chromosomes (and hence nucleic acids). It was also intended to mark Hart-shorne s studies of DSCG (which although by no means the first such mesophase system to be explored, was one of the most extensively examined), and it is to Norman Hartshome, who taught me and many others a love of optical microscopy, that I respectfully dedicate this chapter. 

Lavretovich, O. D. Schneider, T. Golovin, A. B. Lee, J. C. A design and fabrication of an aligned lyotropic chromonic liquid crystal films with improved optical properties and aUgmnent uniformity. U.S. Pat. Appl. Publ. US 2006040069, 2006 Chem. Abstr. 2006,144, 243534. 

---