” Glassy ” and plastic crystals of cyanoadamantane : a Brillouin scattering investigation
نویسندگان
چکیده
2014 The elastic constants of cyanoadamantane have been measured in the plastic and « glassy » crystal phases. A special attention has been given to the temperature evolution of C11 as well as to the damping of the corresponding mode. Comparison with neutron results shows a strong dispersion at room temperature. The temperature dependence of C11 in the plastic phase has been explained by the setting-up of a local antiferro ordering of molecules. J. Physique Lett. 46 (1985) L-617 L-621 ler JUILLET 1985, 1 Classification Physics Abstracts 61.50 61.40D 78.35
منابع مشابه
Local molecular order in the glassy crystalline phase of cyanoadamantane : diffuse X-ray scattering analysis
2014 This Letter presents the results of X-ray scattering experiments performed on cyanoadamantane in its plastic phase (I) and its « glassy crystal » state (Ig) obtained by the quenching of phase (I). The patterns associated with this latter phase are more structured and are characterized by the presence of narrow spots at the X boundary points. An interpretation is proposed in terms of geared...
متن کاملLocal Order and Non Equilibrium Behaviour in Glassy Crystal Cyanoadamantane
During isothermal annealing in the glassy crystal phase. cyanoadamantane relaxes towards a metastable state. The microstructure of the latter is described. I t is di f ferent from t h a t o f the stable phase at the same temperature. The kinetics of ordering which are coupled to a volume contraction are analyzed in terms of molecular relaxation. The "glassy crystals" / 1 / which are obtained by...
متن کاملStructural aspects of the glassy phase of cyanoadamantane
2014 The cyanoadamantane molecule crystallizes in a plastic cubic phase at room temperature and displays a crystalline « glassy phase » by rapid cooling below the glassy phase transition temperature Tg = 170 K. In both cases the cell is f.c.c. with average space group Fm3m (Z = 4). Their structures are solved at 295 and 110 K in the framework of rigid body molecules. Two descriptions are used t...
متن کاملBrillouin scattering investigation of ME6N liquid crystal in CCl4
Available online 3 August 2009
متن کاملComprehensive Theoretical Study on Threshold Power of Stimulated Brillouin Scattering in Single-Mode Fibers
We have investigated and developed a theoretical approach to explore stimulated Brillouin scattering (SBS) phenomena in single mode fiber. SBS happening threshold power condition has been studied in terms of fiber parameters and input pump power. To assess threshold power precisely, the pump depletion effect and fiber loss has been included by employing 1% criterion. The threshold exponential g...
متن کامل