Shape-shifting molecule

Magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy reveals how the supramolecular structure of a lipophilic guanosine derivative can change as the structures passing between the solid state into solution state (in chloroform) and vice versa. This seems paradoxical as a self-assembled structures formed through specific intermolecular hydrogen bonds in solution should remain the same in the solid state. "A systematic study for complexation with different cations and anions emphasizes that the existence of a stable solution or solid-state structure may not reflect the stability of the same supramolecular entity in another phase," the team reports.