Experimental and Theoretical Studies of Acetatodi(methylcyano)bis(o,o′-Dialkyl and Alkylene Dithiophosphate)gadolinium(iii) Novel Adducts

Seven novel Gd(OAc)[S2P(OR)2]2·2CH3CN and Gd(OAc)[S2P(OR′)2]2·2CH3CN gadolinium complexes where R=Et, n-Pr, n-Bu and Ph and R′=CH2CMe2CH2, CH2CEt2CH2, and CMe2CMe2 were synthesized and characterized by elemental analyses, Molecular weight determinations, IR and UV Visible spectroscopy. Micro analytical data revealed a 1:2 metal–ligand (O,O′-dialkyl and alkylene dithiophosphate) molar ratio in all complexes. Geometries were fully optimized at the Semi Empirical Sparkle PM6 level of theory and geometrical structures and electronic properties of the complexes were evaluated. The optimized geometries were confirmed to be minima on the potential energy surfaces through frequency calculations. Linear and nonlinear static optical susceptibilities for all complexes were calculated at the same level of theory. The absorption spectra of the complexes have been established using ORCA2.9 package utilizing the predicted optimized wave functions. The polarizability invariants were, in general, well-correlated with the molecular volume and the number of carbon atoms within the alkyl moieties. The largest electric properties were exhibited by the phenyl dithiophosphate complex.