Absorptionsänderungen von Chlorophyll-b im elektrischen Feld / Absorption Changes of Chlorophyll-b in the Electric Feld

Abstract

In order to test recent interpretations of field indicating absorption changes in photosynthesis, the influence of the electric field on the absorption spectrum of chlorophyll-b is measured in vitro. 50 monomolecular layers of chlorophyll-b are built up on quartz slides by the technique of Blodgett and Langmuir. Absorption changes induced by an electric field linearly increasing from −1.8 · 10⁶ V/cm to +1.8 · 10⁶ V/cm are detected by a repetitive photometer. The absorption changes can be separated into one part, which is proportional to the electric field strength, and a second one, which is proportional to the square of it. The linear change of absorption in the region at ~650 nm may be interpreted as a shift of the absorption band of about .