Standard MP Research Articles

New developments in the model potential method: ScO molecule

An extension of Huizinaga’s model potential method is presented and applied to the study of the equilibrium geometry of the ground electronic state of ScO. In the extended model potential method (EMP) the exchange interaction between the outer core and valence shells are handled more efficiently than in the standard MP method; furthermore, the long range behavior of the model potential is now independent on the reduction of the valence basis set. Using the new method, agreement with all electron results can be achieved in the difficult case of ScO molecule within 0.01 Å in Re, 20 cm−1 in ωe, 0.1–0.2 eV in the binding energy, and an order of 10−3 a.u. in the valence orbital energies.

An exercise in basis inversion

At the NATO conference on Large Scale Decomposition in Cambridge, England, July 1972, it appeared to me that few people knew how matrix inversion is really done in standard MP systems with product form. So I concocted an example and used part of my talk time to run through it. Several people appreciated this and Mike Grigoridis suggested I should put it in the Newsletter. He also wanted it for his own use. My apology to him for the long delay in organizing and typing it, but here it is.