Atomistic simulation on the phase stability, site preference and lattice parameters for LaCo13-xTx (T = Cr, Mn, V, Ti) and LaCo13Hx

摘要

The phase stability, structural parameters, and site preference of LaCo13-xTx (T = Cr, Mn, V, Ti) and LaCo13Hx are studied by using interatomic potentials based on Chen's lattice inversion technique. The results show that the ternary elements can decrease the cohesive energy markedly. It is proved that these elements can stabilize LaCo13-xTx with the NaZn13 structure. Also, we study the volume variation of LaCo13Hx with different temperature. After introducing H atoms, lattice constants and volumes of the compounds are increased significantly. Moreover, the hydrogen atoms preferentially occupy 24d sites. The calculated results indicate that the inverted pair potentials are valid for studying the structural properties of these kinds of materials and some related hydrides. (C) 2008 Elsevier B.V. All rights reserved.