Crystal packing in metal complexes of 4 '-phenylterpyridine and related ligands: occurrence of the 2D and 1D terpy embrace arrays

The crystallisation and resulting crystal structures of complexes [M(4'-Ph-terpy)(2)](PF6)(2) (4'-Ph-terpy = 4'-phenyl-2,2' : 6',2 ''-terpyridine) are described. Three crystal structure types retain the 2D terpy embrace (2D-TE) layers common in crystals of unsubstituted [Mterpy)(2)](2+) complexes, while one structure type has the phenyl substituents intercalated into the 2D-TE, generating 1D terpy embrace chains. Where the 2D-TE is retained there are edge-to-face (EF) or offset-face-to-face (OFF) interactions between the phenyl substituents in the interlayer domain which also contains solvent, while in the intercalated structure the phenyl substituents engage the outer pyridyl rings of terpy in EF and OFF interactions. Anions occupy the major grooves, as usual. Solvent identity is influential, but enigmatic.