Knowledge Bank

The action of $AgF2$ on $S4N4$ in $CCl4$ produces a gaseous compound, $NSF3$, whose structure has been in some doubt. A pure sample was prepared. Fragments in the mass spectrum show that the molecular structure is probably $FN-SFF$ as most recently claimed by Glemser. The microwave spectrum was studied in the region 8,000 to 60,000 me with a conventional Stark modulated spectrograph. The spectrum has the simplicity and first order Stark effects characteristic of a symmetric top. From lines assigned to the normal and also to the $\mathrm{<mrow\; data-mjx-texclass="ORD">34</mrow>}S$ and $\mathrm{<mrow\; data-mjx-texclass="ORD">15</mrow>}N$ species occuring in natural abundance, the following set of structural parameters was obtained: d(S--N) = 1.416 {\AA}, d(S--F) = 1.552 {\AA}, and . The above structure is thus confirmed.