One-dimensional antiferromagnetic chain in [Ni(dmit)(sub ](super -) salts of [K(super +) or Rb(super +)(4,13-diaza-18-crown-6)] supramolecular cation

Mixed-stack structures of monovalent [Ni(dmit)(sub 2)](super -) and planar M(super +)(4,13-diaza-18-crown-6) (M(super +) = K(super +) or Rb(super +)) supramolecular cation are obtained in the isostructural M(super +)(4,13-diaza-18-crown-6)[Ni(dmit)(sub 2)] salts. The mixed-stack structure decreases the effective pi-pi overlap of [Ni(dmit)(sub 2)](super -) molecules, which results in the one-dimensional Heisenberg antiferromagnetic linear chain of S = 1/2 spins within the crystal.