Ionic complexes containing C60•- radical anions and metalloporphyrins coordinatively bound to N,N′,N′- trimethylpiperazinium cations {(TMP+)2•M IITPP}• (C60-)2 (C 6H4Cl2)2 (C6H 5CN)2 [M = Zn (1) and Mn (2)] have been obtained. The crystal structures of 1 and 2 solved at 250 and 270 K, respectively, show layered packing in which fullerene layers alternate with the (TMP +)2 MIITPP ones. Fullerenes form pairs in the layer with short center-to-center distances of 10.044 and 10.077 Å, respectively. The structures of 1 and 2 solved at 100 K indicate the formation of singly bonded (C60-)2 dimers. That results in the transition of 1 from the paramagnetic to diamagnetic state accompanied by the disappearance of the electron paramagnetic resonance (EPR) signal of C 60•- at 220-150 K. Dimerization in 2 results in a decrease in the magnetic moment from 6.36 to 6.00 μB at 200-150 K and a change in the shape of EPR signal. The room-temperature EPR signal shows a major broad component at g = 2.0678 (ΔH = 111.6 mT) attributed to both paramagnetic C60•- and high-spin (TMP +)2•MnIITPP species having strong exchange interaction. After dimerization, the signal is characteristic of isolated high-spin MnIITPP (g⊥ = 6 with |A| = 7.3 mT and g|| ≈ 2). Two TMP+ cations can coordinate to M II in (TMP+)2•MIITPP. However, a weak coordination bond is formed only with one cation with the M II⋯N(TMP+) distances of 2.489(2)-2.688(3) Å. As a result, metal atoms displace by ±0.232(3) Å (1, 250 K), ±0.231(1) Å (1, 100 K) and ±0.4684(7) Å (2, 270 K) out of the porphyrin plane to be located above and below the porphyrin plane with equal occupancies for both positions. The symmetry of the crystal structure of 2 decreases from monoclinic to triclinic under cooling. That results in unequal 0.85/0.15 occupation of the MnII positions at 100 K with displacement of the metal by 0.391(2) and 0.554(4) Å, respectively. © 2010 American Chemical Society.