Metal-assisted salphen organic frameworks (MaSOFs) are known to possess high affinities to CO₂ due to Lewis acidic metal sites and are therefore able to selectively adsorb CO₂ over CH₄ or N₂. By aligning two metal centers in a carefully designed geometry, a "single molecular trap" (SMT) effect is generated, resulting in an interaction of two metal centers with one molecule CO₂ by synergic effects. A condensation of a rigid triptycene based trissalicylaldehyde with tetrammino benzene is used to realize these metal alignments into MaSOFs. Characterization of the discrete trinuclear complexes proves that the chosen geometry is nearly optimal for synergic CO₂ adsorption. The corresponding MaSOFs show high selectivities of CO₂ against CH₄ with a selectivity S_IAST (according to the Ideal Adsorbed Solution Theory) of up to 13 and a selectivity of S_IAST up to 70 against N₂, which are also reflected by isosteric heat of adsorptions (Q_st) of up to 35 kJ/mol. Density functional theory (DFT) calculations support the hypothesis by geometry optimized models and furthermore show a positive cooperative effect by an energy gain of ∼14 kJ/mol during the adsorption of CO₂ in the second binding pocket of the trinuclear metal-salphen compared to a monomolecular adsorption.