CALCULATION OF MAGNETIC PROPERTIES OF HF, H2O, NH3, AND CH4 MOLECULES USING A LONGITUDINAL GAUGE FOR THE VECTOR POTENTIAL

摘要: A transformation of the transverse Coulomb vector potential was implemented to calculate molecular magnetic properties via random-phase approximation (RPA) within framework a “longitudinal gauge.” In this gauge, diamagnetic contribution susceptibility is tensor with equal diagonal components as in atoms, irrespective symmetry, whereas and average contributions nuclear shielding are same gauge. Near-Hartree–Fock tensors were evaluated for set small molecules, HF, H2O, NH3, CH4, employing extended Gaussian basis sets. The peculiar features longitudinal fulfillment series sum rules involving virial operator, which must be satisfied guarantee gauge invariance total tensors, exploited check degree convergence theoretical values estimate corresponding Hartree–Fock limit properties. © 1998 John Wiley & Sons, Inc. Int J Quant Chem 66: 31–45,