First‐principles calculation of second‐order elastic constants and equations of state for lithium azide,LiN3, and lead azide,Pb(N3)2

First‐principle techniques are used to calculate the second‐order elastic constants and equations of state for lithium azide, LiN₃, and lead azide, Pb(N₃)₂. The bulk modulus is calculated for these systems in two independent ways and results compared. The Hartree–Fock potential and density‐functional theory are used for the exchange correlation with different basis sets to examine the effects of each on the elastic constants and bulk modulus. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010