
%0 Journal Article
%A Beecham, AF 
%A Fock, W 
%A Mathieson, AM 
%T The relationship of &#949;<sub>L</sub> and &#949;<sub>R</sub> from consideration of bisignate C.D. curves of &#945;,&#946;-unsaturated ketones
%J Australian Journal of Chemistry
%D 1984/04/01
%V 37
%N 4
%P 667-677
%K 
%R https://doi.org/10.1071/CH9840667
%U https://www.publish.csiro.au/paper/CH9840667 
%X From reconsideration of experimental evidence of &#8710;&#949; and &#949; curves and extrapolation of comments by Beecham and Collins1 it is concluded that the occurrence of bisignate n- &#960;* c.d. curves for ketones and &#945;,&#946;-unsaturated ketones does not require hypothesizing the existence of two spectral bands of opposite sign and therefore indicates that the relationship between &#949;L and &#949;R for a single transition does not necessarily involve a simple constant amplitude factor as the conventional interpretation holds. An alternative interpretation of bisignate curves is proposed, based on one spectral band, the relationship between &#949;L and &#949;R involving differential half-widths of the vibronic components of the L series relative to the R series and a variable relative-amplitude scale along the vibronic progression. If appropriate scale and differential half-width parameters are used, the characteristics of monosignate and bisignate curves can be demonstrated by means of synthetic curves. 
