A paradigm shift in supramolecular chemistry has drawn our attention to produce coordination
polymers for anion separation. In this approach, we have successfully synthesized a
one dimensional coordination polymer from combination of U-shaped diamide ligand, namely
N,N -2,6-bis(4-pyridylmethyl)pyridine dicarboxamide (L1) and Zn(NO3)2 in methanol. This
product is obtained as single crystal with formula molecule given by elemental analysis as
{[Zn(L1)2(H2O)2](NO3)2.4H2O}n. In this account, we also describe supramolecular interactions
between this coordination polymer with two selected anions, nitrate and chromate
using combination of experimental and theoretical studies. Observation via FTIR spectra
indicates the presence of two distinctive peaks for Cr-O (931 cm−1
) and N-O (1384 cm−1
)
confirming encapsulation of chromate and nitrate anions in the receptor. X-ray crystallography
reveals the interaction between NH amide with the anions as expected. As resulted
by Gaussian, coordination polymer with nitrate anion is found more stable compared to
chromate with interaction energy 342.2729 kJ/mol.