Open AccessFirst-principles calculations of the mechanical properties of IrB and IrB2
Author(s) -
Zeng Xiao-Bo,
Xiwen Zhu,
Dehua Li,
Zhongjun Chen,
Yingwei Ai
Publication year - 2014
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.63.153101
Subject(s) - pseudopotential , bulk modulus , lattice constant , density functional theory , hydrostatic pressure , shear modulus , condensed matter physics , materials science , electronic band structure , electronic structure , plane wave , thermodynamics , physics , quantum mechanics , diffraction
We have employed ab-initio plane-wave pseudopotential density functional theory to calculate the equilibrium lattice parameters, elastic constants, under the hydrostatic pressures from 0 to 100 GPa for P1 -IrB with Pnma space group and P5 -IrB2 with Pmmn structures. Results show that the P1 -IrB structure is stable, and the incompressibility is enhanced with the increase of pressure. And the elastic constants, bulk modulus, shear modulus for P5 -IrB2 structure exhibit the regular changes under the hydrostatic pressures from 0 to 100 GPa. But when the pressure becomes 50 GPa, the Young's modulus and the lattice constant in the direction b for P5 -IrB2 structure will change exceptionally. Results show that both are not of obvious band gaps in P1 -IrB and P5 -IrB2 electronic structures under zero pressure, because of the covalent effect between Ir and B atoms. The analysis of band structure and the figure of density of states for P1 -IrB and P5 -IrB2 indicate that the two kinds of structure have metal properties.