SPECTRAL PROPERTIES OF CHLOROPHYLL-A MONOLAYERS - MONOLAYERS OF CHLOROPHYLL-A AND PHEOPHYTIN AT A GAS-WATER INTERFACE

Abstract— Surface and spectral properties of chlorophyll a monolayers were studied at a nitrogen‐water interface. Direct spectral analysis of Chl monolayers indicated that compression results in a heterogenous mixture of Chl species. Fourth derivative and difference spectra showed the presence of minor bands at 692, 726 and 748 nm. The state of compression determines the quantity and type of spectral species formed. A Chl monolayer on an acid subphase results in the formation of a long wavelength absorbing species (705 nm) similar to that of pheophytin. The half‐band width, optical density/monolayer, and extinction coefficients of Chl monolayers are given. It is concluded that in the monolayer the formation of various aggregated species of Chl can be induced. Copyright © 1979, Wiley Blackwell. All rights reserved