Flat crown ethers with planar tetracoordinate carbon atoms

Novel flat crown ether molecules have been characterized in silico using density functional theory. Monomer units of Si(2)C(3)with a planar tetracoordinate carbon (ptC) atom have been used as building blocks. Alkali (Li+, Na+, K+, Rb+, and Cs+) and alkaline-earth (Be2+, Mg2+, Ca2+, Sr2+, and Ba2+) metal ions, and uranyl (UO22+) ion selective complexes have also been theoretically identified. The high symmetry and higher structural rigidity of the host molecules may likely impart higher selectivity in chelation. The potential energy surface of the parent elemental composition, Si2C3H2, has been investigated using coupled-cluster (CC) approximation. The molecule with a ptC atom within the latter is a low-lying isomer lying 12.41 kcal mol(-1)above the global minimum at the CCSD(T)/cc-pVTZ level. The crown ether molecules identified here could theoretically be considered the derivatives of the ptC atom isomer. Theoretical binding energies (Delta E; 0 K) and thermally corrected Gibbs free energies (Delta G; 298.15 K) for crown ether molecules have been computed to gauge their binding affinities.

Automated summary

Novel flat crown ether molecules were characterized in silico using density functional theory. The molecules showed higher selectivity in chelation due to their high symmetry and structural rigidity. Theoretical binding energies and Gibbs free energies were calculated to evaluate the binding affinities of the crown ether molecules.