Ab-initio studies of the structural,electronic,optical and magnetic properties of DyMg intermetallic compound

Structural,electronic,optical and magnetic properties of DyMg intermetallic compound are calculated by using the full potential linearized augmented plane wave(FP-LAPW)method employing density functional theory(DFT).The obtained optimized equilibrium lattice constant in stable structure of DyMg(B2 phase)with spin polarized calculations is 7.107 Bohr and that without spin polarized calculations is 7.115 Bohr.The electronic band structure and density of states plots show metallic character of DyMg.The energy-dependent components of dielectric function,refractive index,extinction coefficient,absorption spectra,optical conductivity,energy loss spectra and reflectivity are reported in the energy range 0–20 eV.In DyMg maximum absorption is observed in the range 4–11 eV.The highest optical conductivity peak is observed near 0.78 eV(1589.5409 nm)and maximum energy loss occurs at 11.90 eV which corresponds to~2.8 Hz in ultraviolet region.The obtained total magnetic moment shows that its value decreases with the increase in lattice parameter.

Full potential study of HoMg

In this paper,HoMg is studied in two different phases i.e.B1 and B2.The calculated lattice constants in B1 and B2 phases are 6.39°A and 3.78°A and corresponding energies are−25,648.49 Ry and−25,648.56 Ry,respectively.It is more stable in B2 phase(Pm-3m configuration with no.221).The analysis of the obtained band structure and density of states shows metallic character of HoMg.Detailed information about the elastic properties is also presented in this paper.The calculated values of Cauchy pressure,G/B and Poisson ratio are−10.72,0.58 and 0.26,respectively which indicates that HoMg have brittle character.Calculations for the optical spectra such as the components of dielectric function,refractive index and other parameters of the optical properties are performed in the energy range of 0-20 eV.For HoMg,the main peak of absorption spectra and energy loss function is located at 7.44 eV and 11.76 eV,respectively.Thermal parameters such as Gruneisen parameter,Debye temperature,Specific heat etc.have been reported as a function of pressure and temperature.©2018 Published by Elsevier B.V.on behalf of Chongqing University.