Hi, I'm trying to repeat the ultrasoft core-hole calculation of the Si K-edge in Matteo's paper:
"First-principles calculations of x-ray absorption in a scheme based on ultrasoft pseudopotentials: From alpha-quartz to high-Tc compounds" I haved used the same parameters given in that article (cell size, cutoff energies, kpoints) but the spectrum that I get does not at all look right. Is it possible that this discrepancy is due to the choice of pseudopotentials? For the absorbing atom I am using http://www.quantum-espresso.org/pseudo/1.3/UPF/Si.star1s-pbe-van_gipaw.UPF which I think is the same one used in the paper. For the other atoms I am using the ultrasoft pseudopotentials included with the xspectra SiO2 example (Si_PBE_USPP.UPF and O_PBE_USPP.UPF). Also, I obtained the fermi level from the output of the scf calculation (converted from eV to Ry). Is this the correct way to choose the ef_r parameter? My input files are attached. Regards, Max -------------- next part -------------- A non-text attachment was scrubbed... Name: SiO2.scf.in Type: text/plain charset=us-ascii Size: 5772 bytes Desc: not available Url : http://www.democritos.it/pipermail/pw_forum/attachments/20110706/f6fc6f21/attachment.bin -------------- next part -------------- A non-text attachment was scrubbed... Name: SiO2.xspectra_dip_plane.in Type: text/plain charset=us-ascii Size: 625 bytes Desc: not available Url : http://www.democritos.it/pipermail/pw_forum/attachments/20110706/f6fc6f21/attachment-0001.bin
