Financial support from the Government of Spain through grants ECO2012-32392, ECO2012-34046 and ECO2011-23959; PR2009-0162 and SM2009-0001; the Generalitat of Catalonia through grants 2014-SGR-803 and 2014-SGR-493; and the Xunta de Galicia through grant 10PXIB300177PR is gratefully acknowledged. Caballé also thanks the financial support from the ICREA Academia program.