Hello, I need to do NEB calculations for my system. My system consists of Si 2*2*2 supercell with some Li impurities. Prior to NEB, I am doing a vc-relax calculation to get the minimum energy states for the first and the last images of the NEB. For the vc-relax, I set *ibrav = 1* for the symmetric cubic system. In the results obtained from vc-relax calculation, the cubic symmetry of the system is lost and I get the following call parameters for the initial and final state in the output file.
CELL_PARAMETERS (alat= 20.51108588) 1.011059885 -0.002882944 -0.000008465 -0.002882944 1.011059885 0.000008465 -0.000008492 0.000008492 1.007297719 CELL_PARAMETERS (alat= 20.51108588) 1.004932042 0.000000442 -0.000000442 0.000000442 1.004688370 0.000104290 -0.000000442 0.000104290 1.004688370 Now, I am confused about my input file for the NEB. I can not just directly change the lattice constant by taking the cube root of the new volume obtained. I tried to set* ibrav = 0* and give the cell parameters obtained but I can only enter them once (correct me if I am wrong) and thus, can not incorporate both the set of cell parameters. I would be extremely thankful if anyone could suggest me a way to tackle this difficulty. Thanks Mitul Mundra Final year Dual Degree Student Department of Chemical Engineering IIT Kanpur -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20140206/2a4a72fe/attachment.html
