Excited states of He: the behaviour of interelectronic angular distribution functions

Abstract

Interelectronic angular distribution functions p( theta 12) and 'angular holes' have been examined for correlated descriptions of several excited states of He. One- and two-particle expectation values were determined, including tau -an overall angular correlation coefficient. Although significant differences were observed between the p( theta 12) curves for the singlet and triplet multiplicities of the 2P state, the 'angular holes' were, in all instances, of similar shape to that obtained for the ground state: however, by comparison, the depths of the excited state 'holes' at theta 12=0 were all considerably reduced in value. The detailed structure of the curves enabled observations to be made regarding variations in the electronic shielding of the nucleus and, in particular, allowed a restatement of Hund's multiplicity rule to be substantiated.