Dear Vincenzo Before discussing your setup, I note that you are using the ensemble-DFT approach implemented in cp.x. I suspect (but perhaps I may be wrong), that it cannot be used to propagate ions in a proper (NVT, NPT, ...) molecular dynamics simulation, but only to optimize structures through damped molecular dynamics. Have you tried first to optimize your system by using pw.x instead of cp.x, and some smearing scheme to deal with metallic systems? You could eventually consider (especially if there are no H atoms involved) a Born-Oppenheimer MD with pw.x as a good solution... HTH Giuseppe
On Wednesday 08 May 2013 16:00:01 Vincenzo Verdolino wrote: > Dear all, > > I am dealing with Iron surface catalyst and I'm trying to run MD simulation > with cp.x > > Here is My Input file > > &control > pseudo_dir = '/cluster/home/chab/verdoliv/espresso/pseudo/', > outdir='/cluster/work/scr1/verdoliv/Initial_wavefunction_min/output' > prefix='Initial_wavefunction_min', > title=Initial_wavefunction_min, > calculation='cp', > restart_mode = 'from_scratch', > nstep = 50, > iprint = 10, > isave = 100, > tstress = .FALSE., > tprnfor = .TRUE., > dt = 4.0d0, > etot_conv_thr = 1.d-9, > ekin_conv_thr = 1.d-4, > ndr = 50 > ndw = 51, > / > &system > ibrav= 8, > C=38.9305, A=7.02146, B=8.10768, cosAB=0.0, cosAC=0.0, cosBC=0.0, > nat= 50, > ntyp= 2, > ecutwfc = 80.0, ecutrho = 640.0, > smearing='cs', > occupations='ensemble', > nbnd = 550, > nspin=1, > nr1b=24, nr2b=24, nr3b=24, > / > &electrons > orthogonalization = 'ortho', > startingwfc = 'random', > electron_dynamics = 'sd', > ampre = 0.02, > tcg = .true., > passop= 0.3, > maxiter = 250, > emass = 300, > emass_cutoff = 3.00, > conv_thr=1.d-6 > n_inner = 2, > lambda_cold = 0.03, > niter_cold_restart = 2, > / > &IONS > ion_dynamics = 'none', > ion_temperature = 'not_controlled', > / > ATOMIC_SPECIES > ATOMIC_SPECIES > Fe 1. Fe.pw91-sp-van_ak.UPF > N 1. N.pw91-van_ak.UPF > ATOMIC_POSITIONS angstrom > Fe 3.517670906 2.029585846 0.473063369 > Fe 3.517670906 6.078055744 0.473063369 > Fe 0.010178272 0.000000000 0.479139716 > Fe 0.010074125 4.053800000 0.476810499 > Fe 4.689525652 0.000000000 1.143911287 > Fe 4.690724988 4.053800000 1.146913875 > Fe 1.178101394 2.026148930 1.147504081 > Fe 1.178101394 6.081492660 1.147504081 > ... > ... > N 2.348065911 4.053800000 10.444508962 > N 2.349799703 4.053800000 11.564212110 > > --------------------------------------------------------------------------- > - > > The output file says > > > PERFORMING CONJUGATE GRADIENT MINIMIZATION OF EL. STATES > cg_sub: missed minimum, case 3, iteration 2 > cg_sub: missed minimum, case 3, iteration 3 > cg_sub: missed minimum, case 1, iteration 5 > cg_sub: missed minimum, case 1, iteration 8 > cg_sub: missed minimum, case 1, iteration 10 > cg_sub: missed minimum, case 1, iteration 11 > cg_sub: missed minimum, case 1, iteration 13 > cg_sub: missed minimum, case 1, iteration 14 > cg_sub: missed minimum, case 1, iteration 16 > cg_sub: missed minimum, case 1, iteration 18 > cg_sub: missed minimum, case 1, iteration 20 > cg_sub: missed minimum, case 1, iteration 22 > cg_sub: missed minimum, case 1, iteration 23 > cg_sub: missed minimum, case 1, iteration 25 > cg_sub: missed minimum, case 1, iteration 27 > cg_sub: missed minimum, case 1, iteration 28 > cg_sub: missed minimum, case 1, iteration 30 > cg_sub: missed minimum, case 1, iteration 32 > cg_sub: missed minimum, case 1, iteration 34 > > > Could any of you give my hints on this field? > > Thanks in advance > > Vincenzo ******************************************************** - Article premier - Les hommes naissent et demeurent libres et ?gaux en droits. Les distinctions sociales ne peuvent ?tre fond?es que sur l'utilit? commune - Article 2 - Le but de toute association politique est la conservation des droits naturels et imprescriptibles de l'homme. Ces droits sont la libert?, la propri?t?, la s?ret? et la r?sistance ? l'oppression. ******************************************************** Giuseppe Mattioli CNR - ISTITUTO DI STRUTTURA DELLA MATERIA v. Salaria Km 29,300 - C.P. 10 I 00015 - Monterotondo Stazione (RM) Tel + 39 06 90672836 - Fax +39 06 90672316 E-mail: <giuseppe.mattioli at ism.cnr.it> ResearcherID: F-6308-2012