Theoretical studies of radical spin arrangements in the cavity of nano-porous complexes

Adsorption properties of magnetic species in nano-porous crystals were studied theoretically. The crystal [Rh 2 bza 4 pyz] n , which had been reported by Mori, Takamizawa and their co-workers in detailed, was employed in this study. As adsorbed magnetic radicals, a oxygen molecule (O 2 ; S = 1) was treated. From the results by our MO calculations, weak magnetic interactions between O 2 molecules in cavities existed. Two types of magnetic interactions (ferro- and antiferro-magnetic) made alignment of trimer spin structure. Our theoretical calculations analyzed not only position but also orientation of the adsorbed O 2 molecules. For the position, cloud of mass densities of O 2 molecules by MD simulation showed stacking styles in nano-pores statistically. Number of adsorbed gas was estimated to be 3.00 molecules/unit. For the orientation, a certain adsorbed O 2 molecule was stabilized by contribution of the two next O 2 molecules as well as four phenyl groups.