Abstract

A detailed quantum mechanical study of ground state sodium cation (Na+) affinities (SCA) and some associated
parameters of conjugated α,β-unsaturated carbonyl compounds (acrolein [ACL], 4-hydroxy-2-nonenal [HNE],
methyl vinyl ketone [MVK], acrylamide [ACR], methyl acrylate [MA], and ethyl methacrylate [EMA]) has been
computed in gas phase and in different solvents (water, dimethyl sulfoxide, CCl4) phase using DFT [B3LYP]
method employing 6-311G (d,p) basis set. Sodium complexes are stabilized by solvation in all cases. ACR exhibits
the highest SCA in all medium. In gas phase, computed Na+ affinity of the compounds are in following order ACR
> MA > HNE > MVK ≥ EMA > ACL whereas upon solvation it shows different trend, follow ACR ≥ MA > EMA
≥ MVK> ACL ≥ HNE order. Sodium cation basicity (SCB) has been calculated from Gibbs free energies obtained
in frequency calculation at the same level of theory. Calculated SCA and SCB values in gas phase are higher in
comparison to the solvent phases. Entropy of the complex formation reactions has been estimated. Atomic charges
of the complexes have been calculated in two schemes Mulliken population analysis and natural population
analysis. The interactions sodium cation (Na+) with ligand is electrostatic ion-dipole interaction in all case. The
local stereochemical disposition of the Na+ is found to be almost same in each case.