A Semiconducting Cationic Square‐Grid Network with FeIII Centers Displaying Unusual Dynamic Behavior

Abstract

The synthesis, structure and properties of a 2D FeIII network material of composition [Fe(O‐bipy)2Cl](TCNQ)2 (O‐bipy = 4,4'‐bipyridyl N,N'‐dioxide; TCNQ = 7,7,8,8‐tetracyanoquinodimethane) are presented. The structure consists of a square grid in which square pyramidal FeIII centers are linked to four equivalent centers through O‐bipy ligands. Pairs of TCNQ radical anions are located within rectangular cavities of the 2D network. The apical position on each Fe center is occupied by a chloride ion. Magnetic studies are indicative of weak antiferromagnetic coupling. Electrical conductivity measurements reveal that the compound is a semiconductor and on the basis of DFT calculations it is proposed that electrical conduction occurs via charge hopping between interlayer TCNQ anions. Mössbauer spectra indicate a rare example of the Goldanskii–Karyagin effect and are suggestive of unusual dynamic processes.