Precise Fixation of an NO molecule inside Carbon Nanopores: A Long-Range Electron-Nuclear Interaction.

A [60]fullerene-based carbon nanopore was synthesized to realize the placing of two molecules of nitric oxide (NO) at an accurate distance. A linear orientation of the two NO molecules inside the assembled nanopores was confirmed crystallographically. Theoretical studies suggested the possible free rotation inside the carbon nanopore while two conformations of NO were predicted to be dominant with keeping its long axis to the orifice of the nanopore. The paramagnetic shifts caused by NO showed a major contribution from the Fermi contact mechanism. The Solomon-Bloembergen theory was found to well describe the paramagnetic relaxation enhancement of the H2O molecule even under equilibrium, which stems from the NO molecule fixed with a distance of ca. 12 A, demonstrating a long-range bimolecular magnetic interaction.