The molecular and electronic structures, stabilities, bonding features, and magnetoresponsive properties of three-membered [c-Ln 3 ] 1/0/2 (Ln 5 La, Ce, Pr, Nd, Gd, Lu) and heterocyclic six-membered [c-Ln 3 E 3 ] q (Ln 5 La, Ce, Pr, Nd, Gd, Lu; E 5 C, N; q 5 0 or 1) rings have been investigated by means of electronic structure calculation methods at the DFT level. The [c-Ln 3 ] 1/0/2 clusters are predicted to be bound with respect to dissociation to their constituent atoms, the estimated binding energies ranging from 45.8 to 2056.4 kJ/mol. The [c-Ln 3 ] rings capture easily a planar three-coordinated nitrogen atom at the center or above the center of the ring yielding the lanthanide nitride clusters [c-Ln 3 (l 3 -N)] adopting a planar geometry, except [c-La 3 (l 3 -N)] which exhibits pyramidal geometry. The [c-Ln 3 (l 3 -N)] clusters are predicted to be bound, with respect to dissociation to N ( 4 S) atom and [c-Ln 3 ] clusters in their ground states, the binding energies ranging from 53.9 to 257.9 kcal/mol. The six-membered [c-Ln 3 E 3 ] q rings are predicted to be bound with respect to dissociation to LnE q monomers in their ground states with dissociation energies in the range of 173.8 to 318.0 kcal/mol. Calculation of the NICS zz -scan curves of the clusters predicted a ''hermaphrodic'' magnetic response of the [c-Ln 3 ] 1/0/2 and heterocyclic six-membered [c-Ln 3 E 3 ] q rings, manifested by the coexistence of successive diatropic (aromatic) and paratropic (antiaromatic) zones. The [c-La 3 ] 1/0/2 and [c-Lu 3 ] 2 are predicted to be weakly antiaromatic, the [c-Lu 3 ] 0/1 , [c-Lu 3 C 3 ] 1 , and [c-Lu 3 N 3 ] double (r1p) aromatic, and the [c-Gd 3 C 3 ] and [c-Gd 3 N 3 ] 1 rings (r1d)-aromatic systems.