Ab Initio Investigation of Structural and Electronic Properties of ErPb3 in AB3 Structure

2016 ◽  
Vol 28 ◽  
pp. 39-42 ◽  
Author(s):  
Shubha Dubey ◽  
Gitanjali Pagare ◽  
Ekta Jain ◽  
Sankar P. Sanyal
Keyword(s):  
Bulk Modulus ◽  
Total Energy ◽  
Electronic Properties ◽  
Density Of States ◽  
Experimental Results ◽  
Energy Calculation ◽  
Present Calculation ◽  
Full Potential ◽  
Local Spin Density Approximation ◽  
Calculated Density

The structural properties and electronic properties of the intermetallic compound ErPb3 which crystallize in AuCu3 type structure (AB3) are studied by means of first principles total energy calculation using full potential linearized plane wave method (FP-LAPW) within the generalized gradient approximation of Perdew, Burke and Ernzrhof (PBE) and local spin density approximation (LSDA) for the exchange correlation functional and including spin magnetic calculation. The total energy is computed as a function of volume and fitted to the Birch-Murnaghan equation of state. The ground state properties of this compound such as equilibrium lattice parameter (a0), bulk modulus (B), and its pressure derivative (B’) are calculated and compared with the available experimental results. We find good agreement with the other theoretical and experimental results. For the compounds, the values of lattice constants obtained by PBE-GGA overestimates and by LSDA underestimates the available experimental values for the same, which verifies the reliability of the present calculation. The value obtained for the bulk modulus is 50.63 GPa. The analysis of electronic properties is achieved by the calculation of the band structures and the density of states in both the spin up and spin down modes, which show a metallic character of ErPB3 due to zero band gap. The values of calculated density of states are found to be 0.36 eV/states and 11.46 eV/states in spin-up and spin-down mode respectively. The calculated magnetic moment (μm) of ErPb3 is 2.06.

First Principles Based Study of Ground State and Electronic Properties of TmPb3 Intermetallic Compound

2016 ◽  
Vol 28 ◽  
pp. 43-46
Author(s):  
Gitanjali Pagare
Keyword(s):  
Intermetallic Compound ◽  
Bulk Modulus ◽  
Electronic Properties ◽  
Density Of States ◽  
Ground State ◽  
First Principles ◽  
Density Functional ◽  
Full Potential ◽  
Electronic Band ◽  
Calculated Density

The ground state behavior of rare earth intermetallic compound TmPb3, which crystallize in AuCu3 type structure, has been examined using first principles density functional theory based on full potential linearized augmented plane wave (FP-LAPW) method. Very few study on structural and electronic properties of TmPb3 compound has been available in the literature, which motivated us to perform the present study. The spin polarized calculations are carried out within the PBE-GGA and LSDA for the exchange correlation (XC) potential. Our calculated ground state properties such as lattice constant (a0), bulk modulus (B) and its pressure derivative (B’) are in good agreement with the experimental results. The value of bulk modulus of TmPb3 is found to be 44.32 GPa and 55.01GPa by PBE-GGA and LSDA respectively. The electronic band structure (BS) and density of states (DOS) verify the metallic nature of this compound. The calculated density of states at the fermi level is found to be 0.16 states/eV and 19.50 states/eV for spin-up and spin-down modes respectively. The magnetic moment of TmPb3 is found to be 0.95.

Ab Initio Study of Pressure Induced Structural, Magnetic and Electronic Properties in Plutonium Pnictides

2014 ◽  
Vol 1047 ◽  
pp. 11-17 ◽  
Author(s):  
Chandrabhan Makode ◽  
Jagdeesh Pataiya ◽  
M. Aynyas ◽  
Sankar P. Sanyal
Keyword(s):  
Bulk Modulus ◽  
Total Energy ◽  
Electronic Properties ◽  
Ambient Pressure ◽  
Structural Phase ◽  
Tight Binding ◽  
Energy Band Diagram ◽  
Lattice Parameter ◽  
Local Spin Density Approximation ◽  
Type B

We have investigated the pressure induced structural and electronic properties of plutonium pnictides (PuY, Y= P, As, Sb). The total energy as a function of volume is obtained by means of self-consistent tight binding linear muffin-in-orbital (TB-LMTO) method within the local spin density approximation (LSDA). From present study with the help of total energy calculations (spin polarized) it is found that PuP, PuAs and PuSb are stable in NaCl – type structure under ambient pressure. The structural stability of PuP, PuAs and PuSb changes under the application of pressure. We predict a structural phase transition from NaCl-type (B1-phase) to CsCl-type (B2-phase) structure for these Pu-pnictides in the pressure range of 20.8 – 42.0 GPa. We also calculate the lattice parameter, bulk modulus, band structure and density of states. From energy band diagram it is observed that all the three compounds exhibit metallic behaviour. The calculated equilibrium lattice parameters and bulk modulus are in good agreement with available experimental data.

Electronic Properties and Formation Mechanism of Metallo-Carbohedrenes

1994 ◽  
Vol 349 ◽  
Author(s):  
Yoshiyuki Kawazoe ◽  
Bing-Lin Gu ◽  
Mark van Schilfgaarde ◽  
Jing-Zhi Yu ◽  
Kaoru Ohno
Keyword(s):  
Electronic Properties ◽  
Density Of States ◽  
Density Functional ◽  
Local Density ◽  
Full Potential ◽  
Mulliken Population ◽  
Calculated Density ◽  
Single Cage ◽  
Atomic Orbitals ◽  
Local Density Functional

ABSTRACTWe have calculated the structure and electronic properties of several metallo-carbohedrenes within the local density-functional approximation, using both methods of a linear combination of atomic orbitals and full-potential muffin-tin orbitals. The calculated density of states and Mulliken population of double cage Ti14C21 and triple cage Ti18C29 are quite similar to that of single cage Ti8C12. There is no additional cohesion in multicage structure, which may explain why there is not a strong tendency to form larger, multi-cage structures. A new stable structure for Ti8C12 is also proposed and structures Ti10C12+x (x=1, 2, 3, 4, 5) have also been discussed.

Full Potential Lmto Study of Tial Alloy

1990 ◽  
Vol 186 ◽  
Author(s):  
Pradeep K. Khowash ◽  
David L. Price ◽  
Bernard R. Cooper
Keyword(s):  
Bulk Modulus ◽  
Total Energy ◽  
Young’S Modulus ◽  
Excellent Agreement ◽  
Tial Alloy ◽  
Lattice Parameters ◽  
Energy Calculation ◽  
Full Potential ◽  
Total Energy Calculation ◽  
Experimental Values

AbstractWe have used a full potential all electron LMTO total energy calculation with a true interstitial to establish a baseline understanding of pure γ-TiAl. The c and a lattice parameters, Bulk modulus and the Young's modulus are calculated and found to be in excellent agreement with reported experimental values.

First-Principles Total Energy Study of NbCr2 + V Laves Phase Ternary System

1998 ◽  
Vol 552 ◽  
Author(s):  
Alim Ormeci ◽  
S. P. Chen ◽  
John M. Wills ◽  
R. C. Albers
Keyword(s):  
Ternary System ◽  
Total Energy ◽  
Density Of States ◽  
First Principles ◽  
Laves Phase ◽  
Full Potential ◽  
Self Consistent ◽  
Substitutional Defects ◽  
Cohesive Energies ◽  
Formation Energies

ABSTRACTThe C15 NbCr2 + V Laves phase ternary system is studied by using a first-principles, self-consistent, full-potential total energy method. Equilibrium lattice parameters, cohesive energies, density of states and formation energies of substitutional defects are calculated. Results of all these calculations show that in the C15 NbCr2 + V compounds, V atoms substitute Cr atoms only.

First-Principles Study of the New Half-Metallic Ferromagnetic Quaternary-Heusler Alloys NaXNO (X=Ca, Sr, Ba)

SPIN ◽  
2020 ◽  
Vol 10 (03) ◽  
pp. 2050022 ◽  
Author(s):  
K. Belkacem ◽  
Y. Zaoui ◽  
S. Amari ◽  
L. Beldi ◽  
B. Bouhafs
Keyword(s):  
Magnetic Properties ◽  
Density Of States ◽  
First Principles ◽  
Density Functional ◽  
Heusler Alloys ◽  
Exchange Potential ◽  
Energy Calculation ◽  
Full Potential ◽  
Electronic Band ◽  
Half Metallic

The first-principles approach based on density functional theory (DFT) and the full-potential linearized augmented plane-wave method were employed to investigate the structural, elastic, electronic and magnetic properties of Na[Formula: see text]NO ([Formula: see text], Sr and Ba) quaternary half-Heusler alloys. The generalized gradient approximation (GGA) as parameterized by Perdew, Burke and Ernzerhof (PBE) and the modified Becke–Johnson exchange potential were used. As far as we know, we present our results which for the first time quantitatively account for the electronic structures and magnetic properties of Na[Formula: see text]NO ([Formula: see text], Sr and Ba) quaternary half-Heusler alloys. From the total energy calculation using three possible atomic configurations ([Formula: see text], [Formula: see text] and [Formula: see text]), it is found that the Na[Formula: see text]NO ([Formula: see text], Sr and Ba) quaternary half-Heusler alloys are more stable in the ferromagnetic [Formula: see text]-phase. From our estimated elastic constants [Formula: see text], it is found that all the considered Heusler alloys are mechanically stable in the [Formula: see text]-phase. We have also investigated the robustness of the half-metallicity with respect to the variation of lattice constants in these alloys. We have found that these alloys are half-metallic ferromagnets (HMFs) with a magnetic moment of 2[Formula: see text][Formula: see text] per formula unit at their equilibrium volumes. The spin-polarized electronic band structure and density of states of these quaternary half-Heusler alloys calculated by GGA (mBJ-GGA) show that the minority spin channels have metallic nature and the majority spin channels have a semiconductor character with half-metallic gaps of 0.49[Formula: see text]eV (2.17[Formula: see text]eV), 0.72[Formula: see text]eV (2.28[Formula: see text]eV) and 0.96[Formula: see text]eV (2.22[Formula: see text]eV) for NaCaNO, NaSrNO and NaBaNO quaternary half-Heusler alloys, respectively. Analysis of the density of states and the spin charge density of these quaternary alloys indicates that their magnetic moments mainly originate from the strong spin-polarization of 2[Formula: see text] states of N atoms and O atoms.

Electronic Structure vs Phase in Al3V

1988 ◽  
Vol 141 ◽  
Author(s):  
J.-H. Xu
Keyword(s):  
Electronic Structure ◽  
Bulk Modulus ◽  
Total Energy ◽  
Crystal Structures ◽  
Lattice Constant ◽  
Density Of States ◽  
Phase Stability ◽  
Local Density ◽  
Young Modulus ◽  
Good Agreement

AbstractThe electronic structure of Al3V vs its two different crystal structures (DO22 and Ll2) were investigated using local density total energy approach. The calculated results of the total energy showed that in Al3V the tetragonal DO22 phase is energetically favored as compared to the cubic Ll2 phase, the total energy in the former case is about 60 mRy/F.U. lower than that in the later case. The calculated lattice constant (a=3.72 Å, c=8.20 Å) is in fairly good agreement with experiment (a=3.778 Å, c=8.326 Å),and the bulk modulus (1.3 Mbar) is comparable with the experimental Young modulus (150 GPa) for Al3Ti. Furthermore, it is interesting to note that the density of states at EF in the tetragonal DO22 phase (0.14 states/eV-F.U.) is about one order magnitude smaller than that in the Ll2 phase (2.89 states/eV-F.U.). The electronic structure of Al3V seems to be fairly satisfactory in explaining its phase stability.

Electronic properties of austenite and martensite Fe-9%Mn alloys

Open Physics ◽  
2008 ◽  
Vol 6 (4) ◽  
Author(s):  
Ercan Uçgun ◽  
Hamza Ocak
Keyword(s):  
Total Energy ◽  
Electronic Properties ◽  
Lattice Relaxation ◽  
The Self ◽  
Full Potential ◽  
Generalized Gradient ◽  
Plane Wave Method ◽  
Lattice Constants ◽  
Generalized Gradient Approximation ◽  
Self Consistent

AbstractWe calculate the electronic properties of austenite and martensite Fe-9%Mn alloys using the self consistent full-potential linearized-plane-wave method under the generalized gradient approximation full lattice relaxation. By minimizing total-energy, the lattice constants in their ground states were determined. We discuss the total energy dependence of the volume, and density of states (DOS).

FAVORABLE SILICA MONOLAYER STRUCTURES ON THE Mo(112) SURFACE

2005 ◽  
Vol 12 (03) ◽  
pp. 449-456 ◽  
Author(s):  
I. N. YAKOVKIN
Keyword(s):  
Total Energy ◽  
Density Of States ◽  
Energy Minimization ◽  
Phonon Frequency ◽  
Experimental Results ◽  
Minimization Technique ◽  
Oxygen Atoms

Favored structures of SiO n monolayers on Mo (112) surface have been studied using the total energy minimization technique based on DFT semirelativistic approach. In the [ SiO 4] complexes, which form the c (2 × 2) silica structure on the Mo (112), the bonding of the Si atoms with the surface is accomplished through the oxygen atoms. The structure with a symmetric position of oxygen atoms has been found to be the most favorable. In this structure, two oxygen atoms occupy bridge-on-row sites on the Mo (112) surface, with Si atoms between them, while oxygen atoms in the troughs appear not in expected threefold sites, but adjust their positions along the middle lines of the troughs. Estimated main phonon frequency and density of states for the symmetric [ SiO 4] structure agree well with experimental results.

Sign in / Sign up

Export Citation Format

Share Document