Marek Sikorski, Miquel Mir and Francis Wilkinson
The phosphorescence decays of β-cyclodextrin (β-CD) complexes of xanthione (XT) and 4H-1-benzopyran-4-thione (BPT) show that self-quenching and oxygen quenching are not important in such complexes, and that the existence of bimodal inclusion in solid complexes can be identified using the width of the distribution parameter of the Gaussian distribution of the logarithm of the observed rate constants for decay.