Spin zinc compounds

The dilution of the spin crossover system in a similar host lattice with bigger ions (e.g. an iron system in the corresponding zinc compound) will create a negative image pressure. The HS state becomes preferentially stabilised and consequently Tc decreases. Simultaneously the conversion curve xHs versus T becomes more gradual. Analogous behaviour is exhibited by [Fe M1 (2-pic)3]Cl2 EtOH systems (M = Co, Zn) and [Fe Mi (phen)2 (NCS)2] systems (M = Mn, Co, Zn). 

Table4.1-143 Spin-orbit splitting energy Aso of zinc compounds...

Manganese is the first transition metal for which + 2 is the common oxidation state—a feature of the remaining first row transition metals from iron to zinc. By comparison with its two neighbours to left and right—chromium and iron—manganese(II) is more stable than expected. This is commonly ascribed to the stable half-filled d electron shell of the high spin compounds. 

As a biologically relevant example of solid-state NMR on quadrupolar nuclei. Fig, 11 shows experimental and simulated Zn solid-state NMR spectra of zinc diimidazole diacetate which may be considered a model compound for Zn in metalloproteins. The experimental spectrum was obtained by sampling the FID in between the refocusing pulses in a quadrupolar version of the Carr-Purcell-Meiboom-Gill experiment (QCPMG), 5 In this manner, the hundred kHz wide second-order quadrupolar powder pattern is split into a manifold of spin-echo sidebands with the consequence of highly... 

Table 3. Vertical ionization energies / (in eV) of gaseous zinc(II), cadmium(II) and mercury (II) compounds. The lowest / corresponds to a M.O. with symmetry type (and oj = 3/2 in spin-orbit coupling) mainly consisting of halide n pn orbitals (carbon a in the case of dimethylmercury). Further on, the d-like components at high / are given in two groups (separated by a semi-colon) with 2Ds/2 at lower and 2D3/2 at higher /.

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