Designing Magnetic Superalkalis with Extremely Large Nonlinear Optical Responses

Predicting superatoms with multiple desired properties is of great interest and challenge. To achieve this goal, a series of organometallic M@36adz (M = Sc ∼ Zn) complexes have been obtained by embedding the 3d transition-metal atoms into the 36adamanzane (36adz) complexant. Under the intramolecular interaction between M and 36adz, the magnetic moments of M atoms are either enhanced or preserved in the resulting M@36adz complexes. Also, the αSOMO levels of M@36adz are significantly raised by the presence of the M impurities, resulting in their greatly lower adiabatic ionization energies (AIEs) of 1.78–2.56 eV than the IE (3.89 eV) of Cs atom. As a result, these complexes can be regarded as a new kind of magnetic superalkalis. Moreover, due to the existence of diffuse electrons in their αSOMO, most of the M@36adz complexes also exhibit remarkable nonlinear optical responses with large first hyperpolarizabilities (β0) of 1.56 × 106–6.33 × 107 au. Hence, this study provides a possible strategy to design a new kind of multifunctional species with high reducing ability, magnetic properties, and large NLO responses by doping various transition metals into such cage-like organic complexants.