LiK-edge soft-x-ray absorption in LiF

The properties of LiF have attracted the attention of theorists for several decades, and previous workers have often regarded the properties of this solid as being somewhat like those of the hydrogen atom: That is, it was assumed that LiF was understood. The purpose of this theoretical study of the soft-x-ray edge of the Li ion in LiF is to demonstrate that this view is unwarranted. This paper concentrates on the effects of exciton structure and multiplicity on the Li $K$-shell absorption to argue that the simple picture of the LiF soft-x-ray properties may need revision. It is argued that some recent and some old experiments are in accord with the conclusions of this work.