Dear Wei
> &system > ibrav= 7, celldm(1) = 5.6298, celldm(3) = 1.4, nat= 2, ntyp= 2, > ecutwfc =30, input_dft='pw91' > / > ATOMIC_SPECIES > Mg 24.305 Mg.pw91-np-van.UPF > O 15.999 O.pw91-van_ak.UPF You are using ultrasoft pseudopotentials. You should explicitly assign a value to the ecutrho parameter (&system list). The default value is 4*ecutwfc, and it is a good value for norm conserving PPs. A 6*ecutwfc~10*ecutwfc value is considered as a safe~good one in the case of ultrasoft PPs HTH Giuseppe -- ******************************************************** - 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>
