Linear-Chain Behavior of the Spin-½ Copper Saltα-bis (N-Methylsalicylaldiminato)-Copper(II)

The spin-½ linear-chain system $\alpha$-bis ($N$-methylsalicylaidiminato)-copper(II) has been investigated by two techniques to elucidate its one-dimensional behavior. First, room- and low-temperature structural information as determined by x-ray diffraction points out that the Cu(II) spin-½ ions are ordered in a linear arrangement 3.33 Å apart along the chain with a large 9.19-Å separation between chains. Then electron-spin-resonance (ESR) data are presented to show that the magnetic system is also one dimensional. The relevant ESR data are the linewidth anisotropy and the line shape at several orientations. Both of these quantities measured by ESR show marked differences from normal three-dimensional behavior and are explained in terms of a one-dimensional model.