Abstract
The optical absorption spectrum of evaporated beryllium films has been measured using an UHV ellipsometric technique. The beryllium films were formed on sapphire substrates held at RT and about 20K but the observed spectra appear to be largely independent of the substrate temperature. It is believed that the data in both cases are to be associated with disordered microcrystalline or amorphous beryllium. It is therefore surprising that present data are so similar to the spectrum obtained on bulk single crystal beryllium by Weaver et al (1973). The paradox is resolved if it is assumed that the details of the electron band structure of crystalline as well as disordered beryllium are governed by short range order; theoretical arguments by Rousseau et al (1970) support this point of view.