Empirically Determined Wave Function for the Relaxed-Excited State of theFCenter in KI

A well-defined probability density has been extracted from measured hyperfine frequencies; it corresponds to a pure $|2p〉$ state peaking at a radius of 6.84 Å. The associated wave function is of a dynamic Jahn-Teller type, such that the orbitals $|x+iy〉$, $|x-iy〉$, and $|z〉$ are equally represented. The radiative lifetime calculated from this state agrees well with the experimentally measured one. The probability density also correctly predicts the known resonance linewidths in KI, KBr, and possibly KCl.