Thanks Giuseppe, I’ll give it a try, I didn’t think about setting the occupation from input. Thank you for your help.
Best, Filippo Filippo Savazzi, PhD Student Politecnico di Torino, Torino, Italy > On 21 Nov 2018, at 19:00, Giuseppe Mattioli <giuseppe.matti...@ism.cnr.it> > wrote: > > > Dear Filippo > Isolated open-shell atoms are tricky. Please look here for hints > > yourpathtoQE6.3/PW/examples/example05 > > HTH > Giuseppe > > Quoting Filippo Savazzi <filo.sava...@gmail.com>: > >> Dear QE users, >> >> I’m Filippo Savazzi, a PhD student from Politecnico di Torino, Italy. >> I’m using QE since a couple of years, and just browsing the archives of this >> mailing list or enquiring the mighty google I’ve been lucky enough that this >> is actually the first time I have to post a question. >> Thanks everybody for the indirect support you gave me in these years. >> >> I’m calculating absorption energies of oxygen on a coronene molecule, as >> part of a little evaluation of different available XC functionals that I’m >> doing. I’m calculating the absorption energy both with respect to the >> molecular oxygen and with atomic oxygen. >> My problems arise when I try to calculate the energy of a single atom of >> oxygen using SCAN. In this case the energy diverges until the SCF fails. I >> have no troubles running the calculation on the actual system (coronene + >> bridged O), neither on a molecular oxygen (triplet O2); the issue is just >> localised on the single oxygen atom. My first guess was that the >> implementation of SCAN has either troubles in dealing with isolated systems >> or with spin polarization, but I ruled out these issues when I was able to >> calculate the single point energy of an oxygen molecule. Are you aware of >> any other problems using SCAN in these conditions? >> In the following I attach the input for pw.x I’m using, as well as a brief >> example of the SCF part in the output. I already played with cell dimension >> (thinking too much vacuum could have been the problem), as well as with >> ecutwfc and ecutrho (so indirectly with the integration grid), and then, >> just to give it a chance, with the diagonalization method and beta-mixing. >> >> Thank you in advance for your attention. >> >> Best, >> Filippo >> >> >> Filippo Savazzi, PhD Student >> Politecnico di Torino, Torino, Italy >> >> >> >> >> &CONTROL >> calculation = ’scf', >> restart_mode='from_scratch', >> pseudo_dir = '/home/filippo/pseudo', >> outdir='./tmp_o', >> prefix='oxy', >> / >> &SYSTEM >> ibrav=6, >> celldm(1)=20, >> celldm(3)=1, >> nat=1, >> ntyp=1, >> input_dft='scan', >> ecutwfc=100, >> tot_magnetization=2, >> nspin=2, >> / >> &ELECTRONS >> diagonalization = 'cg', >> electron_maxstep = 300, >> mixing_mode = 'local-TF', >> mixing_beta = 0.7, >> conv_thr = 1.0d-7, >> / >> &IONS >> ion_dynamics='damp', >> upscale=1000, >> / >> ATOMIC_SPECIES >> O 15.99 O_ONCV_PBE-1.0.upf >> ATOMIC_POSITIONS {angstrom} >> O 0.0000 0.0000 0.0000 >> K_POINTS{gamma} >> >> >> >> >> EXTRACT OF OUTPUT: >> >> Dense grid: 540376 G-vectors FFT dimensions: ( 128, 128, 128) >> >> Estimated max dynamical RAM per process > 116.06 MB >> >> Estimated total dynamical RAM > 1.36 GB >> Generating pointlists ... >> new r_m : 0.4125 (alat units) 8.2500 (a.u.) for type 1 >> >> Initial potential from superposition of free atoms >> >> starting charge 5.99905, renormalised to 6.00000 >> >> negative rho (up,down): 4.917E-05 4.917E-05 >> Starting wfcs are random >> >> total cpu time spent up to now is 3.1 secs >> >> Self-consistent Calculation >> >> iteration # 1 ecut= 100.00 Ry beta= 0.70 >> CG style diagonalization >> ethr = 1.00E-02, avg # of iterations = 9.6 >> >> negative rho (up,down): 1.044E-03 1.363E-03 >> >> total cpu time spent up to now is 240.5 secs >> >> total energy = 2429.63502350 Ry >> Harris-Foulkes estimate = -31.41616940 Ry >> estimated scf accuracy < 3.28037744 Ry >> >> total magnetization = 2.00 Bohr mag/cell >> absolute magnetization = 2.00 Bohr mag/cell >> >> iteration # 2 ecut= 100.00 Ry beta= 0.70 >> CG style diagonalization >> c_bands: 4 eigenvalues not converged >> ethr = 1.00E-02, avg # of iterations = 13.6 >> >> negative rho (up,down): 2.824E-03 3.815E-03 >> >> total cpu time spent up to now is 331.7 secs >> >> total energy = 33638.43350785 Ry >> Harris-Foulkes estimate = 318.68713998 Ry >> estimated scf accuracy < 0.37936007 Ry >> >> total magnetization = 2.00 Bohr mag/cell >> absolute magnetization = 2.00 Bohr mag/cell > > > > GIUSEPPE MATTIOLI > CNR - ISTITUTO DI STRUTTURA DELLA MATERIA > Via Salaria Km 29,300 - C.P. 10 > I-00015 - Monterotondo Scalo (RM) > Mob (*preferred*) +39 373 7305625 > Tel + 39 06 90672342 - Fax +39 06 90672316 > E-mail: <giuseppe.matti...@ism.cnr.it> > > _______________________________________________ > users mailing list > users@lists.quantum-espresso.org > https://lists.quantum-espresso.org/mailman/listinfo/users _______________________________________________ users mailing list users@lists.quantum-espresso.org https://lists.quantum-espresso.org/mailman/listinfo/users