The implementation of a new approach to calculate nuclear magnetic resonance (NMR) chemical shifts at the semiempirical modified neglect of diatomic overlap (MNDO) level was discussed. The gauge including atomic orbitals (GIAO) is used for the implementation purpose. By diagonalizing the complex Fock matrix using a divide-and-conquer strategy, the first-order density matrix with respect to the magnetic field was obtained. It was found that the NMR integral calculations were carried out by expanding STOs in terms of Gaussian functions. For the evaluation of NMR chemical shifts by the MNDO/GIAO method, AM1 optimized geometries were found to be adequate.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry