Intermolecular hydrogen bonding H•••Cl- in the solid palladium(II)-diaminocarbene complexes

Weak intermolecular non-covalent H center dot center dot center dot Cl- interactions in the solid chelated palladium(II)-diaminocarbene complex cis-[PdCl(CNXyl){C(NHXyl) = NHC6 H-2 Me-2 NH2}] Cl (3; Xyl = 2,6-Me2C6H3) were studied by XRD followed by appropriate DFT calculations. The N-H center dot center dot center dot Cl contacts for both NH groups in the carbene moiety are different (N1-H center dot center dot center dot Cl2 3.5258(19), N2-H center dot center dot center dot Cl2 3.0797(17) angstrom). The DFT calculations and topological analysis of the electron density distribution within the formalism of Bader's theory (QTAIM method) were performed for a model cluster of the carbene complex 3. The theoretical data confirmed that the strength of intermolecular HB H center dot center dot center dot Cl- is different for two NH-protons of the carbene fragment. The influence of crystal packing effects on the formation of hydrogen bonds in the cluster of 3 is noticeable.