The relationship between proton-proton NMR coupling constants and substituent electronegativities—I : An empirical generalization of the karplus equation

Ab Initio Methods for the Calculation of NMR Shielding and Indirect Spin-Spin Coupling Constants

Hartree‐Fock perturbation theory of magnetic susceptibility and magnetic shielding is developed using a basis set of gauge invariant atomic orbitals. The theory is used to calculate magnetic shielding and spin‐rotation constants associated with the nuclei in LiH and HF giving results in good agreement with experimental values.

Molecular Orbital Theory of Magnetic Shielding and Magnetic Susceptibility

Spin—spin coupling and the conformational states of peptide systems

Three basis sets (minimal s–p, extended s–p, and minimal s–p with d functions on second row atoms) are used to calculate geometries and binding energies of 24 molecules containing second row atoms. d functions are found to be essential in the description of both properties for hypervalent molecules and to be important in the calculations of two‐heavy‐atom bond lengths even for molecules of normal valence.

Self‐consistent molecular orbital methods. XVII. Geometries and binding energies of second‐row molecules. A comparison of three basis sets

A general method is proposed for quantum‐mechanical study of physical properties of molecules involving polarization or distortion of the electronic structure. This consists of the calculation of self‐consistent molecular orbital wavefunctions (single determinants) in the presence of small but finite perturbations. The general theory of such methods is presented together with a preliminary discussion of numerical error.

Self‐Consistent Perturbation Theory. I. Finite Perturbation Methods

The finite pertubation method developed in the first paper of this series is applied to isotropic nuclear‐spin coupling constants, assuming that only a Fermi contact mechanism couples the electron and nuclear spins. Results for some simple systems are calculated using self‐consistent molecular orbital methods involving the neglect of differential overlap, and on the basis of these results, certain points regarding the mechanisms of spin coupling are discussed. A detailed discussion of the sources and magnitudes of the errors is also presented.

Self‐Consistent Perturbation Theory. II. Nuclear‐Spin Coupling Constants

Approximate self-consistent molecular orbital theory of nuclear spin coupling. I. Directly bonded carbon-hydrogen coupling constants

Approximate self-consistent molecular orbital theory of nuclear spin coupling. II. Fermi contact contributions to coupling between carbon and directly bonded atoms

N. S. Ostlund

Papers

Self‐Consistent Perturbation Theory. I. Finite Perturbation Methods

Self‐Consistent Perturbation Theory. II. Nuclear‐Spin Coupling Constants

Approximate self-consistent molecular orbital theory of nuclear spin coupling. I. Directly bonded carbon-hydrogen coupling constants

Approximate self-consistent molecular orbital theory of nuclear spin coupling. II. Fermi contact contributions to coupling between carbon and directly bonded atoms

Finite perturbation theory for nuclear spin coupling constants