Metal-ligand resonance interaction

Numerical results on metal-ligand resonance interaction... 

Whether of nM 7tL or n- -OL (off-axis) type, pi-backbonding interactions correspond to partial inclusion of ionic resonance structures featuring a metal-ligand double bond, as illustrated schematically in (4.79) for phosphine ligands ... 

Moment reductions have been measured for NiO (56) and for KNiFa (82) by powder diffraction i) and ligand hyperfine interactions in KNiFs (83) and KMgFs (84) by NMR and ESR, and recently in i O-doped MgO by ENDOR (77). The results are given in Table 3. As already mentioned, until the determination of fa =8.5% in MgO, it seemed clear from both the neutron and the resonance data that for this divalent ion, oxides showed similar covalency to fiuorides, with a hgand-to-metal transfer of approximately 0.2e [Eq. (2.23)] (Mn2+, but not Fe3+ data could be similarly interpreted). 

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