Dear all, I tried to perform CP-MD simulations moving electrons beyond the highest KS state. In theory, this can be done using
occupations='from_input' and playing with the OCCUPATIONS card, using a number of bands larger than half of the number of electrons. Here is an example for isolated H2 molecule: # electron steepest-descent &control calculation='cp', restart_mode='from_scratch', prefix='elsd2', pseudo_dir='/home/lapenna/espresso_pseudo/', outdir='/home/lapenna/deloc/H2/./tmp/', ekin_conv_thr =1.e-06, nstep=50, iprint=10, isave=100, dt=2.0, ndr=50, ndw=60, / &system ibrav= 1, celldm(1)= 11, nat=2, ntyp=1, tot_charge=0., ! nelec=2, nspin=1, nbnd=2, ecutwfc = 25.0, ecutrho = 250.0, nr1b = 20, nr2b = 20, nr3b = 20, ! occupations='fixed', occupations='from_input', / &electrons emass = 400., electron_dynamics = 'sd', ! electron_dynamics = 'damp', orthogonalization = 'ortho', ortho_max = 1000, / &ions ion_dynamics = 'none', ion_positions = 'from_input', ! ion_dynamics = 'damp', / ATOMIC_SPECIES H 1.008 H.pbe-rrkjus.UPF ATOMIC_POSITIONS {bohr} H 0.472420E+01 0.472438E+01 0.476847E+01 H 0.472443E+01 0.472425E+01 0.619194E+01 OCCUPATIONS 0.0 2.0 In the output (QE-4.2) I read: ... Wave Initialization: random initial wave-functions Occupation number from init nbnd = 2 0.00 0.00 ... Same occupation numbers every time they are printed, inconsistently with the charge of the system that is zero. Continuing with the dynamics, the H2 dissociation occurs as expected, while with occupations 2. 0. the correct minimum is satisifed. Maybe the comparison between different occupations in CP-MD is nonsense, but this is another story. Why the occupations are all zero beyond the last non-zero from input? Is it a safety measure preventing such hazardous experiments? Also in this latter case, the measure does not work, except in the case of a careful output reading... PW prints occupations as in input. Thank you in advance, Giovanni ============================================================ Giovanni La Penna - National research council (Cnr) Institute for chemistry of organo-metallic compounds (Iccom) via Madonna del Piano 10, I-50019 Sesto Fiorentino, Firenze, Italy tel.: +39 055 522-5264, fax: +39 055 522-5203 e-mail: glapenna at iccom.cnr.it - http://www.iccom.cnr.it/lapenna skype: giovannilapenna ============================================================