Hamiltonian, spin, dimer species

Hamiltonian, spin, dimer species, 31 95 Hamiltonian matrix elements, 25 4, 5, 7, 8, 10 Hammett acidity... 

If the two 0 ions are coupled, the dimer species formed can be expected to exist either as a ground-state singlet or triplet, depending on its nature. In the alkaline-earth oxides, bulk V° centers have been reported these centers consist of a cation vacancy with two hole centers, one trapped either side of the vacancy. Their spectroscopic behavior is characterized as an axial 5 = 1 center and can be described by the spin Hamiltonian,... 

The surface morphology of zirconia and sulfated zirconia were recently studied using NO as a surface probe. When NO was co-adsorbed with molecular oxygen onto activated Zr02, the characteristic EPR spectrum of the O2 radical was observed. More interestingly, Volodin et aV observed a triplet S = 1) spin state due to an NO NO dimer on sulfated zirconia. The species was characterised by the spin-Hamiltonian parameters of = 1-993,3 = 1.942, D = 195 G, and 0 G. At lower NO pressures, the EPR spectra of NO monomers was clearly seen. It was suggested that the symmetry and distance (5.2 A) between two adjacent Zr + ions, was suitable as an adsorption site for the two NO molecules. 

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