Search academic texts

Information × Registration Number 0210U003542, 0108U004136 , R & D reports Title Opto-electronic parameters of ferroics with isotropic point, bulk and nanosized crystals popup.stage_title Head Romanyuk M.O.; Franiv A.V., Registration Date 09-02-2010 Organization Ivan Franko National University of Lviv popup.description2 The spectral and temperature dependences of the refractive indices, birefringence, the piezooptic constants and infrared reflection spectra are investigated; the calculations of the parameters of effective ultraviolet and infrared oscillators, electron polarizability, refraction, as well as the optical constants of both mechanically free and uniaxially stressed dielectric crystals (NH4)2SO4 are crraied out. The influence of phase transitions to an optical anisotropy of a А2ВХ4 ferroic class, TGS and Pb5Ge3O11 crystals and the quantitative parameters of ISB is established; it designed and approved phenomenological approaches for the description of influence of external fields on an optical anisotropy; the influence of a multibeam interference of light on refractive reveals of an optical activity of crystals is investigated. The theoretical investigations, based on self-consistent calculations using pseudopotential method, of the structural and electronic properties of indium and thallium halogenides in a wide pressure range were carried out. The determining role of the cation ns2 electron pair in stabilizing structures with reduced valency is justified. Pressure values of phase transitions to the high symmetry CsCl-type structure and pressure induced transition to a metallic state are determined. The order of structural phase transition in InCl is determined. Product Description popup.authors Бовгира Олег Вікторович Кушнір Олег Степанович Романюк Микола Олексійович Стадник Василь Йосифович Франів Андрій Васильович popup.nrat_date 2020-04-02 Close