Towards the synthesis of the high energy density material TdN4: excited electronic states

Vertical electronic excitation energies for singlet states have been computed for the high energy density material TdN4 in order to assess synthetic routes that originate from excited states of N2 molecules. Based on linear response coupled-cluster calculations, the lowest six excited states are 9.35(1 1T1), 10.01(1 1T2), 10.04(1 1A2), 10.07(1 1E), 10.12(2 1T1), and 10.42(2 1T2) eV above the ground state. Comparison with the energies of excited states of N2+N2 fragments, leads us to propose that the most likely synthetic route for TdN4 involving this mechanism arises from combination of two bound quintet states of N2.