A Model of Magnetic and Relaxation Properties of the Mononuclear [Pc 2Tb]−TBA+ Complex

The present work is aimed at the elaboration of the model of magnetic properties and magnetic relaxation in the mononuclear [Pc 2Tb]−TBA+ complex that displays single-molecule magnet properties. We calculate the Stark structure of the ground 7F6 term of the Tb3+ ion in the exchange charge model of the crystal field, taking account for covalence effects. The ground Stark level of the complex possesses the maximum value of the total angular momentum projection, while the energies of the excited Stark levels increase with decreasing |M J | values, thus giving rise to a barrier for the reversal of magnetization. The one-phonon transitions between the Stark levels of the Tb3+ ion induced by electron-vibrational interaction are shown to lead to magnetization relaxation in the [Pc 2Tb]−TBA+ complex. The rates of all possible transitions between the low-lying Stark levels are calculated in the temperature range 14 K