Magnetic properties of molecules

A major weakness of valence bond theory has been its inability to predict the magnetic properties of molecules. We mentioned this problem in Chapter 7 with regard to the 02 molecule, which is paramagnetic, even though it has an even number (12) of valence electrons. The octet rule, or valence bond theory, would predict that all the electrons in 02 should be paired, which would make it diamagnetic. 

The molecular orbitals are arranged in order of increasing energy. The relative energies of these orbitals are ordinarily deduced from experiment Spectra and magnetic properties of molecules are used. 

Anton, J., Ericke, B. and Engel, E. (2004) Noncollinear and collinear relativistic density-functional program for electric and magnetic properties of molecules. Physical Review A, 69, 012505-1-012505-10. 

D. W. Davies, The Theory of the Electric and Magnetic Properties of Molecules, Wiley, New York, 1967. 

Hinchliffe and Bounds review in detail the calculation of the electric and magnetic properties of molecules. Finally, the use of pseudopotentials in molecular calculations is extending the range of ab initio calculation to molecules containing heavy atoms, and Dixon and Robertson survey this rapidly growing field. 

Rebane, T.K. (1986). Magnetic properties of molecules with closed electronic shells, Up To Day Problems of Quantum Chemistry, Ed. by Veselov M.G., Nauka, Moscow, pp. 165-211. 

H. Hameka, Theory of magnetic properties of molecules with particular emphasis on the hydrogen molecule, Rev. Mod. Phys. 34 (1962) 87. 

G.N. Lewis (1875 -1946 right) created the Chemistry Department at the University of California, Berkeley, and made it into one of the world s best. His other notable work included the first isolation of heavy water (D20), the thermodynamics of solutions, and the phosphorescence and magnetic properties of molecules. 

Ritchie, G.L.D. Field-gradient induced birefringence a direct route to molecular quadrupole moments. In Clary, D.C., Orr, B., (eds) Optical, Electric and Magnetic Properties of Molecules, pg. 67, Elsevier, Amsterdam, The Netherlands (1997)... 

To date, a relatively small number of materials have been explored in a molecular spintronics device and much remains to be understood. For example, the couphng between the molecular layer and the magnetic electrodes is believed to play a very significant role due to the discrete nature of the molecule s HOMO and LUMO, in contrast to the band properties inherent in a continuous-lattice material. The energies of the frontier orbitals with respect to the Fermi level of the electrodes, the broadening of the frontier orbitals into (narrow) bands and the orientation-dependent orbital overlap between molecule and electrode will all contribute to the transport of spins across the interface. Study of the magnetic properties of molecule surface systems is, therefore, highly important and may also lead to new types of spintronic devices. 

P. Lazzeretti, Electric and magnetic properties of molecules, in S. Wilson (Ed.), Handbook of Molecular Physics and Quantum Chemistry, John Wiley Sons, Chichester, to be... 

An excellent source for the study of magnetic properties of molecules is the book by W. 

This is a first-class book, although it presents the state of the art before the ab initio methods for calculating the magnetic properties of molecules. 

A review article on the magnetic properties of molecules (NMR) with presentation of suitable contemporary theoretical methods. 

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