Guest-induced chirality in the ferrimagnetic nanoporous diamond framework Mn3(HCOO)6

Chiral magnets are obtained by inclusion of chiral guest molecules into the channels of an achiral nanoporous ferrimagnet consisting of the Mn-3(HCOO)(6) (1) framework. Insertion of the R or the S enantiomer of 2-chloropropan-1-ol (CH3C*HClCH2OH) in the chiral pores of the previously emptied framework (space group P2(1)/c) results in the two corresponding chiral solids (1R and IS, space group P2(1)), while insertion of a racemic mixture of the two enantiomers retains the achirality of the host for the meso solid (1RS, space group P2(1)/c). The R guest is ordered in the M channels while the S guest is ordered in the P channels. In contrast, the R guests in the P channels and the S guests in the M channels are disordered on two crystallographic orientations. For the racemic mixture of the two enantiomers in 1RS, random disorder of guests in both channels is observed. Thus, the localization of the guest molecule depends on the nature of the surface to recognize the guest of a particular chirality. The guest inclusion compounds are thermally stable. The 1R and 1S compounds are optically active. All the compounds adopt a ferrimagnetic ground state. Compared to the host framework of 1 without guest, the Curie temperature decreases for both 1R and 1S but increases for 1RS. ne additional interactions between the framework and the inserted guest alcohols strengthen the lattice via hydrogen bonds and other electrostatic forces, and it might account for the significant lowering of the lattice contribution as well as the magnetic component to the specific heat capacity upon guest loading.