Crystal Structures, EPR Spectra, and Magnetic Properties of a Series of Ionic Multi‐Component Complexes [(TBPDA) 2 ·(C 60 ·– )·(D + )] (D = Cp* 2 Cr, Cp* 2 Co, TDAE)

New ionic multi‐component complexes [(TBPDA) 2 · (C 60 · – ) · (D + )] [TBPDA = N , N , N′ , N′ ‐tetrabenzyl‐ p ‐phenylenediamine; D = decamethylchromocene (Cp* 2 Cr, 1 ) and decamethylcobaltocene (Cp* 2 Co, 2 )] were obtained additionally to previously characterized [(TBPDA) 2 · (C 60 · – ) · (TDAE · + )] [TDAE = tetrakis(dimethylamino)ethylene, 3 ]. The presence of D + , C 60 · – , and neutral TBPDA in 1 – 3 was proved by the IR and UV/Visible/NIR spectra. D + and C 60 · – form loose layers in 1 and 3 and are spatially separated by bulky TBPDA molecules. The C 60 · – radical anions alternate in the layer with the phenylene groups of TBPDA to form π‐π stacking, whereas disordered Cp* 2 Cr + cations are isolated in the voids formed by eight benzyl groups of TBPDA. The EPR spectra of the complexes show single Lorentzian lines with g = 2.2526 and Δ H = 215 mT ( 1 ), g = 1.9999 and Δ H = 6.7 mT ( 2 ), and g = 2.0009 and Δ H = 2.93 mT ( 3 ) at room temperature. The EPR signal of 2 was attributed to C 60 · – (Cp* 2 Co + is diamagnetic) and those in 1 and 3 to resonating signals between C 60 · – ( g = 1.9996–2.0000) and Cp* 2 Cr + [an asymmetric EPR signal with g [perp] = 4.02(1) and g [par] = 2.001(1)] ( 1 ) or TDAE · + ( g = 2.0035; 3 ) due to indirect coupling. The EPR signals from 2 and 3 are split into two components below 50 and 60 K, respectively, which shift in the opposite directions (to lower and higher fields) with decreasing temperature. The magnetic moments of 1 – 3 decrease below 50–100 K. Both effects are associated with the formation of field‐induced short‐range antiferromagnetically ordered clusters. It is shown that the D + cations do not noticeably affect this interaction. Most probably, it is realized mainly between C 60 · – spins within the layer and is mediated by the phenylene groups of TBPDA. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)