Dear Giuseppe and Ben, I did some work last year looking at a rhombohedral Cr3Al crystal structure. For both Cr.pbe-sp.van.UPF and Cr.pw91-sp-van.UPF, I had difficulty getting accurate results that matched additional calculations I did using all electron approaches (full potential LMTO and KKR).
However, Cyrille Barreteau at CEA-Saclay recently developed some Cr pseudopotential and PAW files that you may want to consider. For my work, the ultrasoft pseudopotential ended up doing a better job then the pseudopotentials note above for bulk Cr. His group also provides some nice comparisons with LCAO methods and details on their construction in the following paper: "Structure and magnetism of bulk Fe and Cr: from plane waves to LCAO methods", J. Phys. Condens. Matt, 22, 295502 (2010). http://http://dx.doi.org/10.1088/0953-8984/22/29/295502 If you are interested, please contact Cyrille to find out more info on the pseudopotentials. Best regards, Derek -- ################################ Derek Stewart, Ph. D. Senior Research Associate http://sites.google.com/site/dft4nano/ 250 Duffield Hall Cornell Nanoscale Facility (CNF) Ithaca, NY 14853 stewart (at) cnf.cornell.edu (607) 255-2856
