Mesomorphic threecoordinate copperi complexes cubtu 2 x, where x cl or br based on a new n benzoylthiourea btu ligand with two decyloxy and one perfluorooctyl groups at its periphery were designed and prepared. This book focuses on the potential for inherently translational research in one field of engineering to radically alter the scope of another. Download product flyer is to download pdf in new tab. Revised manuscript received november 5, 2010 discotic liquid crystals dlcs have been exploited in optoelectronic devices for their advanta. Kaafarani department of chemistry, american university of beirut, beirut 11072020, lebanon received july 29, 2010. In his experiments, reinitzer increased the temperature of a solid sample and watched the crystal change into a hazy liquid. Spherical or quasispherical metallic nps in discotic liquid crystals the dispersion of nanoparticles in dlcs was initiated by kumar and coworkers in 2004 42. In over 2000 pages the handbook provides detailed information on the basic principles of both low and highmolecular weight materials, as well as the synthesis, characterization, modification, and applications such as in computer displays or as structural materials of all. Aug 14, 2018 novel annulated triphenylene discotic liquid crystals generated by pictet. Discotic liquid crystals dlcs have been exploited in optoelectronic devices for their advantageous properties including longrange selfassembling, selfhealing, ease of processing, solubility in a variety of organic solvents, and high charge. The subject of liquid crystals has grown into an exciting interdisciplinary research field with important practical applications. Water molecules, for example, melt directly from solid crystalline ice into liquid water. Handbook of liquid crystals, 8 volume set, 2nd edition. Recent advances in discotic liquid crystalassisted.
Handbook of liquid crystals, 8 volume set, 2nd edition wiley. This site is like a library, use search box in the widget to get ebook that you want. The orientation of liquid crystal molecules could be influenced by application of an electric field. Eports selforganized discotic liquid crystals for high. Introduction to liquid crystals the study of liquid crystals began in 1888 when an austrian botanist named friedrich reinitzer observed that a material known as cholesteryl benzoate had two distinct melting points. Electricfield response of discotic hexabenzocoronene hbc. Solid o all soilds have fix shape, fix volume, ductile and high melting and boiling point. Discotic liquid crystals based on cui complexes with. Discotic liquid crystals s chandrasekhar and g s ranganath raman research institute, bangalore 560080, india abstract recent studies have established that many compounds composed of discshaped molecules exhibit stable thermotropic liquid crystalline phases.
Currently, his research is focused on synthesis and characterization of banana liquid crystals and discotic liquid crystals for solar cells and electro optical applications. A case for discotic liquid crystals in molten triglycerides. A new photoelectrical reorientation effect in nematic liquid crystals has been investigated. Faraday rotation in discotic liquid crystals by longrange electron movement. Jan 24, 2014 discotic liquid crystals dlcs are nanomaterials with sizes ranging from 2 to 6 nm, and they are emerging as onedimensional organic semiconducting materials. Liquid crystals of discshaped molecules, or discotic liquid crystals as they are now. A case for discotic liquid crystals in molten triglycerides robert w. They are now referred to as discotic liquid crystals. Discotic liquid crystals form col mesophases by stacking disclike, often aromatic species into columnar structures that assemble on a twodimensional 2d lattice fig. The first reference book to cover dlcs, chemistry of discotic liquid crystals. The handbook of liquid crystals is a unique compendium of knowledge on all aspects of liquid crystals. The interdisciplinary nature of this text allows for a broad potential readership.
Click download or read online button to get introduction to liquid crystals book now. The confluence of the fields of liquid crystals and biomedical engineering is resulting in remarkable interdisciplinary research. The former liquid crystalline phase appears by changing temperature, and the latter phase appears by changing solution concentration of amphiphilic compounds, etc. Highquality planar alignment of discotic liquid crystals using oscillating shear jaeki kim 1, naoyuki yamasaki, takeshi hayashi, hiroyuki yoshida1, hiroshi moritake2, akihiko fujii 1, yo shimizu3, and masanori ozaki 1division of electrical, electronic and information engineering, graduate school of engineering, osaka university, suita, osaka 5650871, japan. This book presents a systematic and selfcontained treatment of the physics of the different types of thermotropic. Marta martinezabadia, gabriella antonicelli, akinori saeki, manuel mellefranco, aurelio mateoalonso. Recent advances in discotic liquid crystalassisted nanoparticles. Small moleculebased and polymerbased liquid crystals are known.
Discotic materials can also generate a nematic phase and, as for calamitic materials, only one nematic phase exists. Design concepts and synthesis of discotic liquid crystals structure and physical properties of columnar liquid. Liquid crystal molecules are directionally oriented, but positionally not oriented. This book presents a systematic and selfcontained treatment of the physics of the different types of thermotropic liquid crystals the three classical types, nematic, cholesteric and smectic, and the newly discovered discotic type. Hanna yki, institute for surface chemistry, box 5607, stockholm se114 86, sweden, school of nutrition. The discotic liquid crystal hexaperihexabenzocoronene was used in combination with a perylene dye to produce thin films with vertically segregated perylene and. Novel annulated triphenylene discotic liquid crystals. Most thermotropic liquid crystalline molecules have either a calamitic or discotic molecular shape. Nematic discotic left and columnar discotic right liquid crystals a discotic phase in one is which flat molecules typically with threefold or four fold symmetry that have a rigid core and several floppy side chains stacked with their planes lying roughly parallel to one another.
However one advantage is the selfhealing properties of the discotic mesogens. Abstract progress in the field of discotic liquid crystals is summarized, with emphasis on experimental results rather than theoretical developments. Liquid crystal is a state of matter in which the degree of molecular order is intermediate between the perfect three dimensional, long. Discotic liquid crystals dlcs have been exploited in optoelectronic devices for their advantageous properties including longrange selfassembling, selfhealing, ease of processing, solubility in a variety of organic solvents, and high chargecarrier mobilities along the stacking axis. This invention relates to electronic devices including discotic liquid crystals, either doped or undoped, and more specifically to discotic liquid crystals positioned between a pair of opposing first and second electrodes. Formation of a discotic phase requires a discotic aromatic molecule such as phthalocyanine, 6 triphenylene, 7 hexabenzocoronene 8 and so on, although nematic and smectic phases require calamitic molecules. Electronic delocalization in discotic liquid crystals. Download it once and read it on your kindle device, pc, phones or tablets. Liquid crystals organic and printed electronics sigma. From monomers to polymers highlights the chemistry and thermal behavior of dlcs. Electricfield response of discotic hexabenzocoronene hbc liquid crystals wenguang wang, xuying liu and jialing pu laboratory of printing and packaging material and technology, beijing institute of graphic communication, daxing district, xinghuabeilu 25, beijing 102600, china. The discotics such as triphenylenes can stack up but have long tails akyl or alkoxy with c12 groups that allow the discs to remain flexible so they do not become fully crystalline but has a discotic liquid crystal phase. A discotic molecule usually forms a onedimensional columnar structure columnar phase by stacking the molecules.
Discotic liquid crystals dlcs are good candidate organic semiconductors for electronic devices owing to their potential for having a high charge carrier mobility along the columnar axis. Synthesis and characterization of some nonconventional. Both areas have been given little attention despite. The discotic liquid crystal hexaperihexabenzocoronene was used in combination with a perylene dye to produce thin films with vertically segregated perylene and hexabenzocoronene, with large interfacial. This is a new and greatly revised edition of professor chandrasekhars classic book liquid crystals, first published in 1977. Sandeep kumar obtained his phd in medicinal chemistry from banaras hindu university, varanasi in 1986. The effect occurs under the combined application of dc electrical fields and low power illumination.
Liquid crystals of diskshaped molecules, now generally referred to as discotic liquid crystals, were discovered in 1977 chandrasekhar et al. Much more than a slight revision, this second edition of the successful handbook of liquid crystals is completely restructured and streamlined, with updated as well as completely new topics, 100% more content and a new team of editors and authors. Discotic liquid crystals form col mesophases by stacking disclike, often aromatic species into columnar structures that assemble on a twodimensional 2d. Discotic liquid crystals have similar potential to the conducting polymers for their use in photovoltaic cells, they have the same technical challenges of low conductivity and sensitivity to uv damage as the polymer designs. New ionic and polymerizable discotic liquid crystals based on the commercial dye tetraazaporphyrin are presented in chapters 4 and 5. Design and synthesis of novel discotic liquid crystals. Discotic architectures that use a central triphenylene core with six peripheral triphenylene units also exhibit columnar mesophases, and these are commonly called starlike liquid crystals. Classification and examples of liquid crystals cleanenergywiki. Pdf functional discotic liquid crystals sandeep kumar. View discotic liquid crystals research papers on academia. The nanosegregated structures of columnar, smectic and bicontinuous cubic liquid crystals can provide wellorganized, nano and subnanosized 1d, 2d and 3d channels capable of ion and electron. Introduction to liquid crystals download ebook pdf, epub. We offer many welldefined nematic, cholecteric, and smectic molecular liquid crystals, as well as a discotic and several polymeric lc materials.
Abstract when considering the possibility of commercially viable applications for discotic liquid crystals it is worth noting that in the case of calamitic liquid crystals some 80 to 90 years elapsed between their discovery in 1888 and their first application in displays. Description of the liquid crystalline structures 2. Aug 10, 2001 selforganization of liquid crystalline and crystallineconjugated materials has been used to create, directly from solution, thin films with structures optimized for use in photodiodes. Wo1996036082a1 electronic devices based on discotic liquid. Chen, dyesensitized nanoarrays with discotic liquid crystals as interlayer for highefficiency inverted polymer solar cells. There are many different types of liquidcrystal phases, which can be distinguished by their different optical properties such as textures. The various arrangements described may be used in a variety of electronic devices such as temperature sensors, field effect transistors, light sensing devices. Thermotropic and lyotropic liquid crystals are two main classes of liquid crystals. Use features like bookmarks, note taking and highlighting while reading chemistry of discotic liquid crystals. Discotic liquid crystals based on cui complexes with benzoylthiourea derivatives containing a perfluoroalkyl chain monica ilis 1 and viorel circu 1 1 department of inorganic chemistry, university of bucharest, 23 dumbrava rosie st. Discotic liquid crystals dlcs are nanomaterials with sizes ranging from 2 to 6 nm, and they are emerging as onedimensional organic semiconducting materials. Highquality planar alignment of discotic liquid crystals.
The liquid crystal molecules would orient themselves with their dipoles permanent or induced parallel to the field, abonding their previous orientation. The chemical structure of the conjugated core of discotic molecules governs, to a large extent, their. Discotic liquid crystals introduction liquid crystals form a distinctive state of matter. Discotic liquid crystals for optoelectronic applications, bilal r. The synthesis and structural, thermal, optical and theoretical characterization of new tris1,2,4triazolo1,3,5triazines were performed to support their application as liquid crystals and advanced materials. In over 2000 pages the handbook provides detailed information on the basic principles of both low and highmolecular weight materials, as well as the synthesis, characterization, modification, and applications such as in computer displays or as structural materials of all types of liquid. Liquid crystals, sometimes called mesophases, occupy the middle ground between crystalline solids and ordinary liquids with regard to symmetry, energy, and properties. Transport of ions and electrons in nanostructured liquid crystals. Download introduction to liquid crystals or read online books in pdf, epub, tuebl, and mobi format.
Since then, more than discotic compounds have been synthesized and a variety of mesophase structures identified. Divided into six chapters, each with a general description, background, and context for the concepts involved, the book begins with a basic introduction to liquid crystals, describing. The btu ligand coordinates via the s atom in a neutral monodentate fashion as confirmed by ir and nmr spectroscopy data. Liquid crystals lcs are a state of matter which has properties between those of conventional liquids and those of solid crystals. Pdf liquid crystals discotic liquid crystals derived from polycyclic. Selforganization of liquid crystalline and crystallineconjugated materials has been used to create, directly from solution, thin films with structures optimized for use in photodiodes. As such, it fills the gap for a definitive, single source reference for all those working in the field of organized fluids and will set the standard. Design and synthesis of novel discotic liquid crystals by himadri sekhar kayal a dissertation submitted to the faculty of graduate studies. Discotic liquid crystals columnar and nematicmesophases.
For instance, a liquid crystal may flow like a liquid, but its molecules may be oriented in a crystallike way. Liquid crystals are considered as the fourth state of matter after solid, liquid and gas. At present their most important application is in the manufacture of optical compensating films. Easily accessible thermotropic hydrogenbonded columnar discotic liquid crystals from fatty acid trisbenzoimidazolyl benzene complexes. Thus, liquid crystals lcs have been defined as orientationally ordered liquids or positionally disordered crystals that combine the properties of both the crystalline optical and electrical anisotropy. The two key attributes of lcs liquidlike behavior and optical anisotropy drive the majority of lc applications to switchable displays and optoelectronic devices. Discotic liquid crystals for optoelectronic applications. Vorlander in 1908 established his rule that liquid crystalline compounds must have a molecular shape as linear as. Mackenzie1 selforganization of liquid crystalline and crystallineconjugated materials. Wo1996036082a1 electronic devices based on discotic. Discotic liquid crystalnanoparticle hybrid systems npg.
Discotic liquid crystals for selforganizing photovoltaics. Pdf electronic delocalization in discotic liquid crystals. Please inquire for pricing and availability of listed. Liquid crystals and their applications muhammad minhas azeem roll no 7616 govt college university faisalabad department of applied chemistry 2. Examples are given of discotic mesogens including metallomesogens and discotic polymers, and the structures of the mesophases identified to date are described.
Spengler cyclization marichandran vadivel soft condensed matter group, raman research institute, c. Between the crystalline solid and isotropic liquid phases, some compounds demonstrate a distinctly different, intermediate state, also referred to. From monomers to polymers liquid crystals book series kindle edition by kumar, sandeep. Biomimicking with liquid crystals s j woltman et al. Pdf past decades we have witnessed many breakthroughs in research on liquid crystals lcs as well as significant amplification in the. Extension of mcmillans model of smectic a to discotic liquid crystals 4. The journal of physical chemistry c 2019, 123 14, 93829387.
465 506 140 1073 395 1261 1420 229 593 161 171 909 61 1007 379 925 172 133 1033 820 459 352 42 1203 381 388 466 550 1071 290 133 551 494