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'Sustainability' is a ubiquitous term within the political agenda worldwide. The common recognition of such concept has its roots in the Seventies and is the outcome of a cultural process which integrates the 'limits to the (capitalistic) growth' in its paradigm. Notwithstanding, the consistency between 'sustainability' as a concept and its expected contents is doubtful. A trustful approach towards the technical domain, together with the incorporation of 'sustainability' within the market mechanisms, have largely weakened the opportunity for the concept to be disruptive on a political level, locally and globally. The relevant distance between 'sustainability' as a term and its actual contents is the object of the present proposal. The underlying ambiguity of the 'Sustainable Development Goals' will be provided as a case-study for our critical review.

We calculate the optical absorption spectra of prototype (6,6) and (9,9) BN nanotubes in the presence of a perpendicular electric field. This model mimics a gated BN nanotube device. Even though the band-gap of the tubes decreases strongly as a function of the electric field strength, the absorption spectrum of the pure tubes remains remarkably constant up to high field-strength. We show that, in contrast, the levels which are responsible for defect-mediated photo-luminescence are shifted by the electric field. We address the use of BN nanotubes for optoelectronic applications. ; This work has been funded by the EC Network of Excellence NANOQUANTA (Ref. NMP4- CT-2004-500198). C.A. and L.W. acknowledge support from the French National Research Agency (ANR). A.R. acknowledges support from the Spanish Ministry of Education, the SANES (Ref. NMP4-CT-2006-017310), DNANANODEVICES (Ref. IST-2006-029192), and NANO-ERA Chemistry projects, the University of the Basque Country EHU/UPV (SGIker Arina), and the Basque Country Government. ; Peer reviewed

Time-dependent density functional theory (TDDFT) is an efficient method to evaluate excited-state properties of electron systems. However, it is not so well-known that it also provides a very accurate prescription to obtain correlation energies by using the so-called adiabatic connection fluctuation dissipation theorem (ACFDT). In this paper we present a detailed study of the ACFDT performance in bulk solids and jellium clusters. These results confirm the reliability of the ACFDT scheme and pave the way to future applications where standard implementations of the Kohn−Sham density functional theory dramatically fail, in particular to weakly bound systems and van der Waals complexes. ; This work has being funded by the EC Network of Excellence NANOQUANTA (ref NMP4-CT-2004-500198), the Spanish Ministry of Education (grant FIS2004-05035-C03-03), the SANES (ref NMP4-CT-2006-017310), DNA-NANODEVICES (ref IST-2006-029192), and NANO-ERA Chemistry projects, the University of the Basque Country EHU/UPV (SGIker Arina), and the Basque Country Government. The research by JJF and PGG is financed by the Juan de la Cierva and the Ramon y Cajal Programs, respectively. ; Peer reviewed