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This review analyses the results obtained through the Electron Spin Resonance (ESR) spectroscopy on multilayer Langmuir-Blodgett films fabricated with metal derivatives (mainly Cu 2+ , VO 2+ and low-spin CO 2+ ) of polyazamacrocycles (porphyrins, tetraazaannulenes, phthalocyanines). These metal ions are particularly suitable for an ESR analysis because of their relatively long electron spin relaxation times that render possible their observation even at room temperature and in all co-ordination symmetry. This allows us to obtain valuable data on both mobility and orientation of the metal-macrocycle systems adsorbed onto a solid support. The preliminary characterisation of the spreading monolayer obtained from the systems considered, as it is typically done by surface pressure/area isotherms, optical (UV-Vis) and ESR spectroscopies, is also reviewed.

The Langmuir—Blodgett technique has been used for the preparation of magnetic multilayer films of manganese arachidate either as a pure component or in mixture with the diamagnetic methyl arachidate. The mutual surface miscibility of both compounds was verified from the spreading isotherms of their mixtures. The spreading isotherms allowed us to find the optimum conditions for the transfer of monolayers onto silanized quartz plates and to prepare LB films with more than 100 layers. Electron paramagnetic resonance spectroscopy has been used to characterize the magnetic properties of the films. The typical shape anisotropy of quasi-two-dimensional magnets was observed from the orientation dependence in the magnetic field of the linewidth and from the changes of both linewidth and resonance position with temperature at T 5 the usual isotropic properties were observed.