The noble-gas-trapping ability of the star-shaped C5Li 7+ cluster and O2Li5+ super-alkali cluster is studied by using ab initio and density functional theory (DFT) at the MP2 and M05-2X levels with 6-311+G(d,p) and 6-311+G(d) basis sets. These clusters are shown to be effective noble-gas-trapping agents. The stability of noble-gas-loaded clusters is analyzed in terms of dissociation energies, reaction enthalpies, and conceptual DFT-based reactivity descriptors. The presence of an external electric field improves the dissociation energy. Caught in a trap: Ab initio and density functional studies reveal that the Li centers of star-shaped C5Li7+ clusters and O2Li5+ super-alkali clusters can bind noble gas (Ng) atoms effectively (see figure). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.