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The reaction of manganese(III) acetate meso-tetraphenylporphyrin with phenylphosphinic acid provides the one-dimensional compound of formula [Mn(TPP)O2PHPh] x H2O, which crystallizes in the monoclinic C2/c space group. The chain structure is generated by a glide plane resulting in Jahn-Teller elongation axes of the MnIII octahedra that alternate along the chain. The phenylphosphinate anion transmits a sizable antiferromagnetic exchange interaction that, combined with the easy axis magnetic anisotropy of the MnIII sites, gives rise to a canted antiferromagnetic arrangement of the spins. The static single-crystal magnetic properties have been analyzed with a classical Monte Carlo approach, and the best fit parameters for the exchange and single ion anisotropy are J = -0.68(4) K and D = -4.7(2) K, respectively (using the -2JS(i)S(j) formalism for the exchange). Below 5 K the single-crystal dynamics susceptibility reveals a frequency-dependent out-of-phase signal typical of single-chain magnets. The extracted relaxation time follows the Arrhenius law with delta = 36.8 K. The dynamic behavior has been rationalized and correlated to geometrical parameters of the structure. The contribution of the correlation length to the energy barrier has been investigated, and it has been found that the characteristic length that dominates the dynamics strongly exceeds the correlation length estimated from magnetic susceptibility.

Aluminum (III) meso-tetraphenylporphyrins axially bonded to phosphinate anions have been synthesized and characterized by NMR and UV-visible spectroscopy, single-crystal X-ray diffraction, and FAB+ mass spectrometry. According to the solvent and the size of the anion, these compounds are able to self-assemble in two different manners.