DIPOLAR ATOMS IN Na-NaX SOLUTIONS ? -AN OPTICAL STUDY-

Abstract
In a recent quantum molecular dynamics calculation of diluted Na-NaBr solutions Parrinello and coworkers found that excess electrons may localize to form dipolar Na atomic - like states. This is at variance with spectroscopic observations that F-center like states prevail in alkalimetal-alkalihalide solutions. In order to get further insight into this problem we have reinvestigated the optical absorption spectra of dilute alkalimetal-alkalihalide-NaCl solutions as a function of temperature and for various salt compositions. The main result of this study is that indeed in NaCl-rich solutions deviations from the expected F-center characteristics are visible.