Freederiksz Medals awarded to Professor Shibaev and Professor Saupe

Abstract

The Freederiksz Medal was set up in 1997 as an award for outstanding contributions in the fields of physics, chemistry and applications of liquid crystals. The first laureates in 1997 were Professor Viktor Tsvetkov (Russia) and Professor George Gray (UK). The awards for 1998 were announced at a ceremony on November 25 1998 during a session of the Liquid Crystal Society ‘Commonwealth’ held at the Institute of Crystallography, Moscow. The Freederiksz Medal for outstanding contributions in the field of the chemistry of liquid crystals was awarded to Professor Valery Shibaev (Russia), while the Freederiksz Medal for outstanding contributions in the field of the physics of liquid crystals was awarded to Professor Alfred Saupe (Germany). The award was presented at the meeting to Professor Shibaev, but unfortunately, Professor Saupe was unable to be present at the award ceremony. Brief accounts of the contributions of the 1998 Freedericksz Medal laureates are given below.

Valerii Petrovich Shibaev (Moscow State University, Moscow, Russia)     

Acousto-optics of liquid crystals: Yesterday,today, and tomorrow

The most important results of the recent theoretical and experimental studies in the field of acousto-optics of liquid crystals (LCs) in research lines initiated by the pioneering studies of Professor A.P. Kapustin at the Institute of Crystallography of the Russian Academy of Sciences and carried out at the Acoustic Institute of the Russian Academy of Sciences are generalized and analyzed. These lines include the study of the nature of acoustically induced supramolecular structures in nematic liquid crystals (NLCs) and cholesteric liquid crystals (CLCs) and the development of physical bases of practical LC acousto-optics, related to the detection of acoustic signals.     

Photonics of liquid-crystal structures: A review

The original results of studies of the electro-optical and laser effects which have been performed at the Laboratory of Liquid Crystals of the Institute of Crystallography, Russian Academy of Sciences, over the last few years are reviewed. Cholesteric liquid crystals as vivid representatives of photonic structures and their behavior in an electric field are considered in detail. The formation of higher harmonics in the periodic distribution of the director field in a helical liquid crystal structure and, correspondingly, the new (anharmonic) mode of electro-optical effects are discussed. Another group of studies is devoted to bistable light switching by an electric field in chiral nematics. Polarization diffraction gratings controlled by an electric field are also considered. The results of studies devoted to microlasers on various photonic structures with cholesteric and nematic liquid crystals are considered in detail. Particular attention is given to the new regime: leaky-mode lasing. Designs of liquid crystal light amplifiers and their polarization, field, and spectral characteristics are considered in the last section.     

Laboratory of N.V. Belov as a school of highly qualified experts

The occasion of Nikolai Vasil’evich Belov’s 120th birthday is a good reason for recalling the works of this prominent representative of the pleiad of famous Russian and foreign crystallographers. Not only experts in structural crystallography passed through his school. The number of postgraduates that became candidates of sciences (and some, later, doctors) under the guidance of Belov is amazing. Many of his students organized and headed new laboratories at the Institute of Crystallography and at other institutes. We all remember the original methods proposed by Belov for determining the atomic structure of crystals in periods before and after the time when computers arose. New directions in the study of minerals and the solution of structural problems of crystal chemistry, crystal physics, and materials science continue in the community of crystallographers. They are being actively developed, and not only by Belov’s students.     

On the 70th anniversary of the Shubnikov Institute of Crystallography of the Russian Academy of Sciences

We are celebrating the 70th anniversary of the Shubnikov Institute of Crystallography. The institute has gone from being a small laboratory of piezoelectric crystals to a large internationally known scientific center. The 1990s was a decade of ruin, both literally and figuratively, for our institute; however, it is hard to believe that was the case when walking through the corridors of the institute today.     

Crystallization in space: Results and prospects

The results of studying crystallization in space are reviewed with focus on the growth of semiconductor and protein crystals. The history of the problem is considered, the influence of microgravity on the crystal growth is investigated, and the main experimental data on crystal growth in zero gravity are analyzed. The studies performed in this field at the Institute of Crystallography, Russian Academy of Sciences (IC RAS), are reviewed in detail.     

Features of Optical Activity in Inorganic and Organic Materials

Crystallography Reports - The possibilities of manifestation of optical activity in different media (photonic crystals, metamaterials, and liquid crystals) are considered. Some interesting examples...     

Captured Orientational Order in Polymer Network Assemblies

Abstract

The “marriage” between low molecular weight liquid crystals and polymers burgeoned in the 1980s with the idea of dispersing liquid crystal droplets in a rigid polymer matrix to create an electrically controllable light scattering medium. The orientation of the liquid crystal droplets, and hence the refractive index match and scattering, can be systematically controlled with an electric field. Today, dispersions of liquid crystals and polymers are found in many forms depending on the concentration of polymer, which can be as large as 70% or as small as 1%. The systems most understood are those of larger concentration where the liquid crystal is segregated out in the form of droplets randomly distributed throughout the surrounding polymer (see page 2). Dispersions of liquid crystals and polymers differ from macroscopic bulk liquid crystals because of the large surface-to-volume ratio and symmetry breaking non-planar geometry imposed by the polymer. Their composite nature profoundly affects the ordering of the liquid crystal, and their susceptibility to external fields makes them suitable for many new electro-optic applications, as well as intellectually challenging to study from the basic science perspective.     

Gold Medal for Professor Chandrasekhar

Abstract

Professor S. Chandrasekhar, Centre for Liquid Crystal Research, Bangalore, has been nominated by the Niels Bohr Institute for the award of a Niels Bohr-UNESCO Gold Medal in recognition of his ‘outstanding contributions to the development of liquid crystals, the advancement of science in developing countries and the teaching of physics’. The presentation will be made by the Director General of UNESCO, Dr Federico Mayor, during the symposium on Niels Bohr and the Evolution of Physics in the 20th Century to be held in Paris, 27–29 May 1998.     

Methods of crystal optics for studying electromagnetic phenomena in metamaterials: Review

The state of the art of electrodynamics of new composite media—metamaterials—is reviewed. The composites in the form of a periodic lattice of identical elements, which are in essence artificial crystals with characteristic scales of the internal structure from several centimeters to several hundred nanometers are considered. The most important properties of metamaterials and the specific features of propagation of electromagnetic signals in these media are described. Particular attention is paid to the conventional methods of condensed-matter physics, which have found application in the electrodynamics of metamaterials and have provided dynamic development of this new field of science and technology.     

Structural Features Associated with Twinning in the Growth of Gallium Arsenide Single Crystals by the Czochralski Method

Crystallography Reports - The structural features induced by twinning in tin- and tellurium-doped gallium arsenide crystals during their growth by the Czochralski method with liquid melt sealing by...     

Ukranian Liquid Crystal Society

Abstract

The Third Ukrainian Liquid Crystal Conference, was held in Kiev, at the Institute of Physics, 10 and 11 January, 1995. More than 50 delegates, representing 12 liquid crystal scientific and industrial groups working in the Ukraine, discussed the latest achievements in physics, chemistry and application of liquid crystals.     

Circular Dichroism in Cholesteric Liquid Crystals

Crystallography Reports - The circular dichroism in cholesteric liquid crystals (CLCs) has been studied in the absorption bands of dissolved dichroic dyes possessing both the positive and negative...     

Bulk photovoltaic effect in noncentrosymmetric crystals

The theory and the experimental characteristics of the bulk photovoltaic effect in ferroelectric and piezoelectric crystals first observed at the Institute of Crystallography have been reviewed. I dedicate this review to the memory of B.K. Vainshtein whose help in performing these works was really inestimable.     

Acoustic Waves and Supramolecular Structures in Liquid Crystals

Crystallography Reports - The achievements in the study of the supramolecular structures arising in liquid crystals (LCs) under acoustic waves, which was started by the work of Professor А.P....     

Otto Lehman Prize 1999

Abstract

The Otto Lehman Foundation was established in 1997 by Professors Mlynski and Knoll from the University of Karlsruhe, Germany. The mission of the foundation is to promote scientific contributions from the rising generation of scientists in the field of liquid crystals. The prize can be given for outstanding habilitations, doctoral theses and graduate work in fields of liquid crystal science making a significant contribution to the application of liquid crystals.     

Station for X-ray structural analysis of materials and single crystals (including nanocrystals) on a synchrotron radiation beam from the wiggler at the Siberia-2 storage ring

The design of the station for structural analysis of polycrystalline materials and single crystals (including nanoobjects and macromolecular crystals) on a synchrotron radiation beam from the superconducting wiggler of the Siberia-2 storage ring is described. The wiggler is constructed at the Budker Institute of Nuclear Physics of the Siberian Division of the Russian Academy of Sciences. The X-ray optical scheme of the station involves a (1, ?1) double-crystal monochromator with a fixed position of the monochromatic beam and a sagittal bending of the second crystal, segmented mirrors bent by piezoelectric motors, and a (2θ, ω, φ) three-circle goniometer with a fixed tilt angle. Almost all devices of the station are designed and fabricated at the Shubnikov Institute of Crystallography of the Russian Academy of Sciences. The Bruker APEX11 two-dimensional CCD detector will serve as a detector in the station.     

Effect of a Travelling Magnetic Field on the Parameters of Tellurium-Doped Gallium Arsenide Single Crystals Grown by the Czochralski Method

Crystallography Reports - The effect of a traveling magnetic field on the parameters of Te-doped GaAs single crystals in the carrier density range of 5 × 1017–2 ×...     

Electron Diffraction of Microcrystals on the Example of Lysozyme

Crystallography Reports - Electron diffraction of microcrystals is a new powerful tool of cryo-electron microscopy, which makes it possible to determine the structure of three-dimensional crystals...     

The library as an element of the information infrastructure of crystallography (On the 75th anniversary of the library of the Institute of Crystallography of the Russian Academy of Sciences)

The role of a scientific library and, in particular, the library of the Institute of Crystallography of the Russian Academy of Sciences, in the development of crystallography has been considered as well as the place of the library of the Institute of Crystallography in the information flows based on the achievements in modern crystallographic research.