Dear users and developers, I'm using Quantum Espresso 3.2 and would like to reproduce some of the DFT results of C. Rovira et al., J. Phys. Chem. A 101, 8914 (1997) regarding the equilibrium geometries of Iron-Porphyrin (FeP) complexes. However, I find some significant discrepancies: in particular in our equilibrium structure of FeP(Im)(CO), where Im denotes the imidazole group, the FeP plane gets considerably more "domed" with respect to what reported in the above-mentioned reference.
Of course there could be several reasons for this, but in particular I noted that they use XC functional of Becke (exchange) and Perdew (corr) type. They also mention a comparison with BLYP-type functionals. However, since orbital energy structure of the ground state involves d orbitals of Fe, initially I chose the pseudopotentials (in the pwscf site) that include the d orbitals contribution, namely Fe.pbe-nd-rrkjus.UPF or Fe.pz-nd-rrkjus.UPF For the sake of uniformness I used PBE- or PZ-type pseudopotentials also for C, O and N. Now, I wonder if the problem of excessive doming could be due to the use of wrong pseudopotential ... I would like to try with BLYP's but the one for Fe does not seem to include explicitly d orbitals. Are there other sources of pseudopotentials? Thanks in advance for any help. Cristian ___________________________________________________ Cristian Degli Esposti Boschi CNR, CNISM, Unita' di Ricerca di Bologna, c/o Dipartimento di Fisica, Universita' di Bologna viale Berti-Pichat, 6/2, 40127, Bologna, Italia tel. ++39 051 2095114 fax ++39 051 2095113 e-mail: cristian.degliesposti -AT- unibo.it web: http://www.df.unibo.it/fismat/theory ___________________________________________________
