Thank you Gerhard, My idea was to calculate enthalpy of formation of a typical Laves phase AB2 And for all the individual components I used Run_lapw -cc 0.0001 -ec 0.0001 -so -i 90 -p I thought it might work for AB2 as well. But I did not get a smooth variation of the volume with energy. I also used Run_lapw -cc 0.0001 -ec 0.00001 -in1ef -p which work beautifully for Fe_bcc
The idea therefore is two fold; one to get the desired accuracy and the second that nobody should question the result !! SG -----Original Message----- From: wien-boun...@zeus.theochem.tuwien.ac.at [mailto:wien-bounces at zeus.theochem.tuwien.ac.at] On Behalf Of Gerhard Fecher Sent: Wednesday, October 27, 2010 12:34 PM To: A Mailing list for WIEN2k users Subject: Re: [Wien] Querie on the -i switch for iterations_Spin Polarized Cases Do you realy need the charge convergency -cc 0.0001 for the volume optimization ? What for ? For a rough estimate -ec 0.0001 may be fine, you can sharpen the convergency criteria afterwards. Then try for example -cc 0.001 -ec 0.00001 and increase the k-points (copy the clm files don't use charge extrapolation in the second step) check if the relaxed volume is different. Sometimes a lot of 0's don't help a lot. Ciao Gerhard ==================================== Dr. Gerhard H. Fecher Institut of Inorganic and Analytical Chemistry Johannes Gutenberg - University 55099 Mainz ________________________________________ Von: wien-bounces at zeus.theochem.tuwien.ac.at [wien-bounces at zeus.theochem.tuwien.ac.at]" im Auftrag von "Ghosh SUDDHASATTWA [ssghosh at igcar.gov.in] Gesendet: Mittwoch, 27. Oktober 2010 06:45 Bis: 'A Mailing list for WIEN2k users' Betreff: [Wien] Querie on the -i switch for iterations_Spin Polarized Cases Dear Wien2k users, I was trying to volume optimize (some 5 structure changes, 4 atoms per lattice) a cubic case with the command in the optimize.job Runsp_lapw -cc 0.0001 -ec 0.0001 -i 90 -so -p However, in one or two cases, the SCF did not converge. What changes could be made keeping the same accuracy of charge and energy convergence. SUDDHASATTWA GHOSH _______________________________________________ Wien mailing list Wien at zeus.theochem.tuwien.ac.at http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien