Long-range magnetic order in the quasi-1D metalloporphyrin family of molecule-based magnets

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-mu(2)-bonded spin s = 1/2 accepters [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 quantum-classical 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.