First-principles calculation of structure and mechanical property of IrY

The structure, mechanical property and electronic structure of IrY alloy are investigated using the first-principles. The calculated equilibrium lattice parameter of the IrY is in good agreement with the experimental value. The calculated cohesive energy and enthalpies of formation is negative value, implies that the structure is stable at ground state. The electronic structure show that hybridization exist between Ir(5d(7)6s(2)) state and Y(4s(2)4p(6)4d(1)5s(2)) state and the form metallic Ir-Y bonds along the d-d direction. The calculated elastic modulus of IrY alloy represents high bulk modulus and shear modulus. However, this values of G/B (0.446) is close to brittleness-to-ductile (0.500), indicate that the IrY alloy exhibit brittleness behavior compare with the other Ir-Y alloys. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Kunming University of Science and Technology