Dear Gabriele Thank you for your comments in pwscf forum.
I performed your suggestion that ecut is set to 32 Ry. The structure was relaxed and I repeated with ecut=20 , 22 Ry. It seems that the structure did not relaxed with this point " * ............. ........... the Fermi energy is -5.0636 ev ! total energy = -262.94392529 Ry Harris-Foulkes estimate = -262.94392533 Ry estimated scf accuracy < 0.00000006 Ry The total energy is the sum of the following terms: one-electron contribution = -323.90644330 Ry hartree contribution = 178.85727642 Ry xc contribution = -104.02662243 Ry ewald contribution = -13.85257067 Ry smearing contrib. (-TS) = -0.01556530 Ry convergence has been achieved in 2 iterations Forces acting on atoms (Ry/au): negative rho (up, down): 0.998E-04 0.000E+00 atom 1 type 1 force = 0.00000000 0.00223711 0.00000000 atom 2 type 1 force = -0.00165978 -0.00111856 0.00000000 atom 3 type 1 force = 0.00165978 -0.00111856 0.00000000 Total force = 0.003608 Total SCF correction = 0.000988 SCF correction compared to forces is too large, reduce conv_thr The maximum number of steps has been reached. End of BFGS Geometry Optimization Begin final coordinates ATOMIC_POSITIONS (angstrom) Au 0.000000000 0.248435531 0.000000000 Au -2.339313337 1.325352234 0.000000000 Au 2.339313337 1.325352234 0.000000000 End final coordinates* ........................ ........................ Questions : 1) The electron_maxstep is equaled 100. What is purpose of "number of states" ? 2) Should I consider system to be semiconducting If I want to simulate 4-atoms cluster? Best Regards, Reza.Shidpour SUT -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20100913/57452288/attachment.htm