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A noncyanocarbon-based molecule-based magnet [MnIIITPP]+[QCl4].− has been prepared, comprising tetraphenylporphinatomanganese(III), MnIIITPP, and tetrachloro-1,4-benzosemiquinone, QCl4. As structural motif it has a coordination-polymer structure with uniform, one-dimensional linear chains of alternating, albeit disordered, [MnIIITPP]+ cations and [QCl4].− radical anions. Intrachain antiferromagnetic coupling J/kB, −89 K (−62 cm−1, 134 cal mol−1, 7.5 meV) is noted. Two magnetically ordered states at 13 and at 7 K are observed (right).

(meso-Tetrakis(4-chlorophenyl)porphinato)manganese(III) tetracyanoethenide, [MnTClPP][TCNE], has been prepared and structurally characterized as the toluene and dichloromethane disolvates, and the magnetic and thermal properties of these solvates, as well as their corresponding desolvates, have been determined.

The unusual magnetic properties of various members of the quasi-1D manganese-porphyrin family are reviewed. Typical members of the family consist of spin S = 2 Mn III porphyrin ions alternating with trans-μ 2 -bonded spin s = 1/2 acceptors [C 2 (CN) 4 ] − or [C 4 (CN) 6 ] − . All members exhibit 1D behavior at high temperatures as evidenced by their similarities to predictions for mixed quantumclassical ferrimagnetic chains. Below approximately 50 K, deviations from one-dimensionality are observed due to the effects of interchain interactions. The competition between interchain exchange, single-ion anisotropy, and dipolar interactions are considered when examining the remarkable differences in the low temperature magnetic states of the various compounds.

The reaction of meso-tetrakis (4-dimethoxyphenyl) porphinatomanganese(II), MnTPOMeP, with TCNE (TCNE = tetracyanoethylene) leads to the formation of [MnTPOMeP]+ [TCNE]− and [MnTPOMeP]+[OC(CN)C(CN)2]−. The single-crystal X-ray structures of the latter as well as [Cu(bipy)2Cl]+ [OC(CN)C(CN)2]− were determined. The former has a disordered [OC(CN)C(CN)2]− bridging via C and O between a pair of MnIII sites, whereas the latter has an isolated [OC(CN)C(CN)2]− unbound to CuII. The IR characterization for μ2-C,O bound [OC(CN)C(CN)2]− is at 2219m and 2196s (νCN) cm−1 and at 1558s (νCO) cm−1 while for unbound [OC(CN)C(CN)2]− it is at 2210m, 2203m, 2181m (νCN) cm−1 and at 1583s (νCO) cm−1.

We present direct current (dc) magnetization M(T,H) and alternating current (ac) susceptibility χac(T,H,f) data for the quasi‐one‐dimensional molecule‐based ferrimagnet [MnTPP]::+[TCNE].−⋅2PhMe (TPP=meso‐tetraphenylporphyrinato, TCNE=tetracyanoethylene). Static scaling of the real part χ′ of the ac susceptibility and data collapse of M(T,H) over a limited reduced temperature range above Tc≊13 K lead to the critical exponents γ≊1.6, β≊0.5, and δ≊4.2. Below Tc, χac depends sensitively on frequency and exhibits a striking double‐peak structure similar to that found in reentrant spin glasses. Possible models for the frequency dependence of the peaks observed in χac are discussed.