Polynitrogen Chemistry, Synthesis, Characterization, and Crystal Structure of Surprisingly Stable Fluoroantimonate Salts of N5(+).

摘要

The new N5(+) salt, N5(+)SbF6(-), was prepared from N2F(+)SbF6(-) and HN3 in anhydrous HF solution. The white solid is surprisingly stable, decomposing only at 70 deg C, and is relatively insensitive to impact. Its vibrational spectrum exhibits all nine fundamentals with frequencies that are in excellent agreement with the theoretical calculations for a five-atomic V-shaped ion of C2v symmetry. The N5(+)Sb2F11(-) salt was also prepared and its crystal structure was determined. The geometry previously predicted for free gaseous N5(+) from theoretical calculations was confirmed within experimental error. The Sb2F11(-) anions exhibit an unusual geometry with eclipsed SbF4 groups due to inter-ionic bridging with the N5(+) cations. The N5(+) cation is a powerful one- electron oxidizer. Its electron affinity falls between 11.0 and 12.08 eV because it readily oxidizes NO to NO(+) and NO2 to NO2 but fails to oxidize Xe or O2.