text: The authors acknowledge ﬁnancial support from Span- 
  ish MEC (FIS2007-65702-C02-01), “Grupos Consolidados 
  UPV/EHU del Gobierno Vasco” (IT-319-07), e-I3 ETSF 
  project (Contract Number 211956), “Red Espa˜nola de Super- 
  computaci´on”, NABIIT and the Danish Center for Scientiﬁc 
  Computing. The Center for Atomic-scale Materials Design 
  (CAMD) is sponsored by the Lundbeck Foundation. JMG-L 
  acknowledges funding from Spanish MICINN through Juan 
  de la Cierva and Jos´e Castillejo programs. 
  
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