The unsymmetrical tridentate benzimidazole-pyridine-carboxamide units in ligands L1-L4 react with trivalent lanthanides, Ln III, to give the nine-co-ordinate triple-helical complexes [Ln(Li ) 3 ] 3ϩ (i = 1-4) existing as mixtures of C 3 -symmetrical facial and C 1 -symmetrical meridional isomers. Although the β 13 formation constants are 3-4 orders of magnitude smaller for these complexes than those found for the D 3 -symmetrical analogues [Ln(Li ) 3 ] 3ϩ (i = 5-6) with symmetrical ligands, their formation at the millimolar scale is quantitative and the emission quantum yield ofisomerisation process in acetonitrile is slow enough for Ln = Lu III to be quantified by 1 H NMR below room temperature. The separation of enthalpic and entropic contributions shows that the distribution of the facial and meridional isomers can be tuned by the judicious peripheral substitution of the ligands affecting the interstrand interactions. Molecular mechanics (MM) calculations suggest that one supplementary interstrand π-stacking interaction stabilises the meridional isomers, while the facial isomers benefit from more favourable electrostatic contributions. As a result of the mixture of facial and meridional isomers in solution, we were unable to obtain single crystals of 1 : 3 complexes, but the X-ray crystal structures of their nine-co-ordinate precursors [Eu(L1) 2 (CF 3 SO 3 ) 2 (H 2 O)](CF 3 SO 3 )(C 3 H 5 N) 2 (H 2 O) (6, C 45 H 54 EuF 9 N 10 O 13 S 3 , monoclinic, P2 1 /c, Z = 4) and [Eu(L4) 2 (CF 3 SO 3 ) 2 (H 2 O)](CF 3 SO 3 )(C 4 H 4 O) 1.5 (7, C 51 H 66 EuF 9 N 8 O 15.5 S 3 , triclinic, P1, Z = 2) provide crucial structural information on the binding mode of the unsymmetrical tridentate ligands.

The festive meal texts of Deuteronomy 12-26 depict Israel as a unified people participating in cultic banquets -a powerful and earthy image for both preexilic Judahite and later audiences.

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