Electronic spectral studies on Nd³⁺ in different solvent environment: Symmetry of solvato-complex vis a vis solvent nature

257-260Electronic spectra of Nd3+ ion in different solvent environments, viz., water, ethanol, acetic acid, ethylacetate, dimethyl sulphoxide and dimethylformamide have been recorded in order to study the effect of solvato-complex formation on the electronic spectral parameters of Nd3+ ion. The variation in the oscillator strengths (P), Judd-Ofelt parameters (Tλ), the inter-electronic repulsion (Racah) parameters (d Ek) and the nephelauxetic ratio (b =s E3/s E1) values has been examined in the light of nature of the solvent, the mode of Nd - solvent bonding and the Nd – O solvent donor atom bond distance. The spectral parameters show a dependence on the dielectric constant of the solvent. The Tλ parameters show a marked dependence on Nd-O bond distance. The d E3/dE1 values show a gradual increase with decreasing Nd-O bond distance. Coordination number, follows the order, HOH, Et-OH (CN~9) > Et-Ac, Ac (CN 8-9) > DMF, DMSO (CN~8)