Leslie G. S. Brooker

Spatial Configuration, Light Absorption, and Sensitizing Effects of Cyanine Dyes*†

AbstractPhotographic sensitizers may be classified according to the freedom of relative motion of the parts of the molecule as “loose,” “compact,” or “crowded.” The first two of these categories comprise planar and the third non-planar molecules. Compactness is especially favourable for dye aggregation. Sheppards correlation between planarity and strong sensitization is confirmed, and amplified to stress the marked loss of sensitization which can accompany slight distortion from planarity.