Structural criteria for the rational design of selective ligands: convergent hydrogen bonding sites for the nitrate anion.

A large number of crystal structures are analyzed to characterize the structural aspects of hydrogen bonding interactions with the NO(3)(-) anion. Further insight is provided by the use of electronic structure calculations to determine stable geometries and interaction energies for NO(3)(-) complexes with several simple hydrogen bond donor groups, including water, methanol, N-methylform-amide, and methane. The results establish the existence of a clear set of structural criteria for the rational design of molecular receptors that complex the NO(3)(-) anion through hydrogen bonding interactions.