The magnetic anisotropy and electronic structure of binuclear copper (II) acetate monohydrate

The magnetic anisotropy of binuclear copper (II) acetate monohydrate has been redetermined by a null deflexion method at temperatures between 80 and 300 K. The new data establish that all previously reported anisotropy measurements have been seriously in error, presumably due to difficulties in correctly identifying the principal crystal axes. The previous necessity to invoke temperature -dependent values for the exchange integral Jeff and the g-factors now disappears and the new experimental anisotropies conform closely to Bleaney & Bowers (1952 b) theory with constant values for the disposable parameters. The magnetic anisotropy is especially sensitive to anisotropy in the high-frequency term of the susceptibility expressions. This enables the controversial electronic spectrum to be assigned in terms of the ligand field transitions 11000 cm-1 (dz2 ← dx2-y2); 14400 cm-1 (dxz,yz ← dx2-y2); 17000 Cm-1 (dxy ← dx2-y2). The nature of the chemical bonding and exchange interaction is discussed.

[1]  N. Hill,et al.  The insignificance of metal–metal bonding in the antiferromagnetism of copper(II) carboxylate dimers , 1969 .

[2]  S. Kettle,et al.  The importance of metal–metal bonding in the antiferromagnetism of copper(II) acetate monohydrate , 1969 .

[3]  R. Martin,et al.  The π System of Binuclear Copper(II) and Chromium(II) Acetates , 1966 .

[4]  P. Sengupta,et al.  Isotropic exchange integral in copper propionate monohydrate , 1965 .

[5]  B. C. Guha.  Magnetic properties of copper acetate at low temperatures. II , 1965 .

[6]  C. Ballhausen,et al.  Electronic structure of copper acetate monohydrate based on a coupled chromophore model , 1965 .

[7]  H. Flood,et al.  Binuclear Complexes. I. The Electronic Structure of Copper Acetate. , 1962 .

[8]  C. Jørgensen.  CHAPTER 12 – CHEMICAL BONDING , 1962 .

[9]  Y. Tanizaki.  The Degree of Polarization of Dichroic Polarizer of Polyvinyl Alcohol-Iodine in the Region of 240–1000 mμ , 1957 .

[10]  Hidetarō Abe,et al.  Anomalous Magnetic Resonance Absorption of Copper Acetate at 40 kMc/sec , 1953 .

[11]  K. Bowers,et al.  Anomalous paramagnetism of copper acetate , 1952, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[12]  H. Kumagai,et al.  Anomalous Magnetic Resonance Absorption ofCu , 1952 .

[13]  K. Bowers,et al.  Anomalous paramagnetism and exchange interaction in copper acetate , 1952 .

[14]  C. A. Coulson,et al.  XXXIV. Notes on the molecular orbital treatment of the hydrogen molecule , 1949 .

[15]  B. C. Guha.  Magnetic Properties of some Paramagnetic Crystals at Low Temperatures , 1945, Nature.

[16]  K. S. Krishnan,et al.  Diamagnetic Anisotropy of Crystals in Relation to Their Molecular Structure , 1936 .