Lattice Dynamical Properties of the Rare-Earth Dihydrides XH2 (X=Sc, Y, and La)
Journal Title: Asian Journal of Physical and Chemical Sciences - Year 2017, Vol 4, Issue 1
Abstract
The rare-earth hydrides have received tremendous attention due to their potential applications for hydrogen storage technology, they exhibit intriguing electronic, optical, and mechanical properties. In particular, XH2 series (X= Sc, Y, and La), the prototype for rare-earth dihydrides, are very attractive due to their excellent properties: high pressure stability, mechanical strength, favourable kinetics feature, small neutron absorption cross-section, and dramatic optical properties. At ambient conditions, XH2 (X= Sc, Y, and La) crystallize in the cubic fluorite structure with a Fm3m space group, typically having a fcc lattice where the tetrahedral sites are filled with hydrogen atoms. The theoretical investigations of phonon properties of XH2 are scarce as these properties are very helpful to explore the nature of XH2. Besides the structural aspects, the study of their vibrational properties is also important as they are closely related to several fundamental properties such as inter atomic interaction, phonon spectra, specific heat etc. Therefore, in this work a de launey angular force constant model has been used to study the phonons in XH2 (X= Sc, Y, and La) by considering the interatomic interactions up to third nearest neighbor. It is found that the ranges of phonon frequencies for acoustic and optical modes decrease gradually from ScH2 to LaH2. The calculated results are compared and analyzed with available experimental results.
Authors and Affiliations
M. M. Sinha
Mineral and Proximate Composition of Soya Bean
Aims: The aim of the research was to analyse the minerals and proximate content of soya bean in order to explore its nutritional values in human and animal diets. Place and Duration of Study: This study was carried out a...
Equivalent Multiple Complex SUSY For Real SUSY
We notice real SUSY Hamiltonians have multiple equivalent complex Hamiltonians which may be (i) PT invariant (ii) T invariant or (iii) combination of both in nature . These three types of complex Hamiltonians give the sa...
Composition and Frequency Dependent Dielectric Properties of Cr-Co Nano Ferrites
Chromium substituted Co-ferrite nanoparticles with general formula CrxCoFe2−xO4 (0≤ x ≤0.5) have been synthesized by using sol-gel technique. The samples were sintered at 900°C for 3hours. The effect of chromium substitu...
Characterization and Antibacterial Activity of Zinc Oxide Nanoparticles Synthesized Using Opuntia ficus indica Fruit Aqueous Extract
Zinc Oxide nanoparticles were green synthesized by Opuntia ficus indica fruit aqueous extract. The phytochemicals present in the plant extract act as reducing and stabilizing agents. SEM and UV-Vis spectroscopy were used...
Thermoluminescence Characteristics of Different Types of Natural Marble and the Effect of Annealing Temperatures
Aims: This paper presents preliminary results on the characteristics of different marbles from Libya and Jordan. Several samples were collected and analyzed using thermoluminesence (TL) technique. Study Design: Study the...