Knowledge Bank

The electronic spectra of s-tetrazine cooled in a free jet shows three bands which have been attributed to dimers or higher polymers of s-tetrazine. Rotational analysis shows three distinct conformations of these complexes. A parallel band shifted $+140cm-1$ from the s-tetrazine origin is due to a structure with parallel tetrazine rings separated by 4.5 {\AA}, The second band, which is shifted by $-30cm-1$, is a perpendicular transition and is due to a structure with two coplanar tetrazine rings. A band at $-43cm-1$ is currently being studied. Mixed completes- between s-tetrazine and benzene have been observed. One band shifted $+124cm-1$ has a parallel contour which can be fit as a dimer between s-tetrazine and benzene with parallel rings separated by 3.7 {\AA}. A second band shifted $+59cm-1$ is a near prolate top with a B type contour and has been attributed to the trimer s-tetrazine dimer plus benzene van der Waals complex.