SEMICLASSICAL SELF-CONSISTENT-FIELD PERTURBATION-THEORY FOR THE HYDROGEN-ATOM IN A MAGNETIC-FIELD

A recently developed perturbation theory for solving self-consistent f ield equations is applied to the hydrogen atom in a strong magnetic fi eld. This system has been extensively studied using other methods and is therefore a good test case for the new method. The perturbation the ory.yields summable large-order expansions. The accuracy of the self-c onsistent field approximation varies according to field strength and q uantum state but is often higher than the accuracy from adiabatic appr oximations. A new derivation is presented for the asymptotic adiabatic approximation, the most useful of the adiabatic approaches. This deri vation uses semiclassical perturbation theory without invoking an adia batic hypothesis. (C) 1998 John Wiley & Sons, Inc. Int J Quant Chem 69 : 183-192, 1998.