Pentanitrogen cation

N+ and N+, have been observed only as free gaseous or matrix-isolated ions or radicals. The only polynitrogen species synthesized on a macroscopic scale thus far is the pentanitrogen cation Nj by Christe and co-workers in 1999. 

Molecular dimensions of the pentanitrogen cation from crystal structure analysis. 

Table 6 Geometrical parameters of the pentanitrogen cation in Ns+SbjFir...

The synthesis of the pentanitrogen cation (6) marks a milestone in polynitrogen chemistry [32], because this is only the second poly nitrogen to have been actually isolated, as (hstinct from just spectroscopically detected. Salts of the azide ion were first reported in 1890 [27], and salts of the pentanitrogen cation in 1999 [18], The hiatus suggests that the synthesis of polynitrogens involves problems. The first Ns salt used the hexafluoroarsenate counterion ... 

N5+ Pentanitrogen cation Metastable salts only with large counter [19-21]... 

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