The relative stability of nano-“chromic wheels” [Cr n (OCH3)2 n (CH3COO) n ] depending on the number of their coordination units

Abstract: The relative stability of [Cr n (OCH3)2 n (CH3COO) n ] depending on the number n of its interior groups (n =4, 6, 8, 10, 12 and 14) has been studied by means of Hartree–Fock (HF) and Density Functional Theory (DFT) calculations. The calculation schemes employ atom-centered localized basis orbitals. As the first step, the structures of the molecules were optimized by means of quantum-chemistry and molecular mechanics approaches. All the molecules were found to have a lower energy in the anti-ferromagnetic state than in the ferromagnetic one; the total energy per one coordination section E tot/n was calculated for further discussions. The relative stability of [Cr n (OCH3)2 n (CH3COO) n ] molecules for different n, as estimated by the DFT, correlates with a structural rule, which allows the prediction of the relative stability of different ‘wheel’-type compounds by using a simple formula. This study demonstrates that computational chemistry can be useful for theoretical forecasting of new stable molecules of the ‘wheel’-type. This approach can be used for the rational design of molecular systems possessing magnetic properties. [Copyright &y& Elsevier]