Dear PWSCF users, In the paper of S Q Wang et al. J Phys. Cond. Matter 15 (2003) 5307, (attached with this mail) He uses three types of strains
1. Tri-axial shear strain to calculate C44 2. volume conservative orthorombic strain to calculate shear modulus C` and 3. Hydrostatic pressure to calculate Bulk modulus. In my calculations, on applying the 3rd strain, I am getting different volumes for different set of strained lattice vectors (Volume non-conserve) and 1st & 2nd type volume remain same (volume conserved) Because in order to calculate 3 elastic constants (C11, C12 and C44) we require 3 equations, so do I have to use the above three equations, both type (volume conservative and non-conservative) to calculate a single set of elastic constants? please guide me for the same. -- Bipul Rakshit PhD Student, Barkatullah University, Bhopal 462026, MP, India -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20090716/f04cfd1c/attachment.htm
