The temperature dependence of the formyl proton shieldings of 9-anthraldehyde and 9-phenanthraldehyde in chloroform solutions has been measured. Four concentrations in the range 0.5–5.0 mole % were examined over the temperature interval − 60 to + 90 °C. From these results, the enthalpies and entropies of formation have been estimated for the complex formed by the self-association of two aldehyde molecules. The calculations indicate the ΔH and ΔS values to be − 1.9 ± 0.3 kcal/mole and − 6 ± 1 e.u., respectively. These results are compared with other available data.
1H NMR determination of the self-association of an acridine homodimer and its complexation with ethidium bromide in aqueous solution