Induced CD on the d-d transitions of square planar MS4 chromophoric groupsof Ni(II) complexes with enantiomeric dithiophosphate ligands: (+)(589) (-)(CD662) Ni[(R,R)bdtp](2) and (-)(589) (+)(CD662) Ni[(S,S)bdtp](2)

New bis-chelate square-planar complexes of Ni(II) with enantiomeric ligands , cyclo-O,O'-(R,R)- or -(S,S)-1,2-dimethylethylene dithiophosphate ion, hav e been synthesized and characterized via W-vis and CD spectroscopy and an X -ray crystal structure investigation, the results of which have been correl ated. The absence of an intrinsic configurational chirality on the metal ha s allowed to obtain CD spectra due only to the less intense chirality induc ed on the Ni(II) electronic d-d transitions by the ligands outer ring confo rmations and absolute configuration of the 2 and 3 carbon atoms of the two chelating ligands.