Theoretical studies on solid α,ω-diamine salts

The present study reports a structural analysis of the homologous series of alpha,w-diamine dihydrochlorides ([H3N(CH2).NH3](2+)-2Cl(-)) in the solid state, through ab initio molecular orbital calculations. Several molecular models were built and assessed for their ability to accurately represent these systems, which displayed distinct conformational behaviours according to the length of their carbon chain. It was verified that the larger the amines the more intermolecular interactions had to be considered by the theoretical models, from (N)H...Cl and (C)H...Cl close-contacts to weak London dispersion forces.