Interaction of N-acetyl-L-cysteine (NAC) with Pr3+ (Pr(NO3)3·6H2O) and Nd3+ (Nd(NO3)3·6H2O) ions
are studied in presence of Ca2+ (Ca(NO3)3·4H2O) ion in an aqueous and organic solvent by applying
the spectroscopic technique for quantitative probe of 4f-4f transition. The complexation was determined
by the variation in the intensities of 4f-4f absorption spectral bands and by applying the change of
symmetric properties of electronic-dipole known as Judd-Ofelt parameters Tλ (λ = 2,4,6). On the
addition of Ca2+ ion in the binary complexation of praseodymium and neodymium with
N-acetyl-L-cysteine (NAC) there is an intensification of bands which shows the effect of Ca2+ toward
the heterobimetallic complex formation. Other parameters like Slater-Condon (Fk), bonding (b1/2), the
Nephelauxetic ratio (β), percentage covalency (δ) are also used to correlate the complexation of metals
with N-acetyl-L-cysteine (NAC). With the minor change in coordination around Pr3+ and Nd3+ ions,
the sensitivity of 4f-4f bands is detected and further used to explain the coordination of
N-acetyl-L-cysteine (NAC) with Pr3+ and Nd3+ in presence of Ca2+. The variation in oscillator strength
(Pobs), energy (Eobs) and dipole intensity parameter help in supporting the heterobimetallic complexation
of N-acetyl-L-cysteine. In kinetics investigation, the rate of the complexation of both hypersensitive
and pseudo-hypersensitive transition is evaluated at various temperature in DMF solvent. The value of
the thermodynamic parameters such as ΔHo, ΔSo and ΔGo and activation energy (Ea) also evaluated.
Optical Absorption, Kinetics and Thermodynamic Studies of Pr(III) and
Nd(III) Ions with N-Acetyl L-Cysteine in Presence of Ca(II) ions
