Beschreibung:
<jats:title>Abstract</jats:title><jats:p>In hexagonal CdS<jats:sub>1−<jats:italic>x</jats:italic></jats:sub>Se<jats:sub><jats:italic>x</jats:italic></jats:sub> amalgamation‐type mixed crystals the isoelectronic impurity Te is studied as a function of the composition <jats:italic>x</jats:italic> in the range 0 ≦ <jats:italic>x</jats:italic> ≦ <jats:bold>1</jats:bold> by emission and excitation measurements at 4 and 77 K. The binding energies of excitons bound to isolated Te impurities and nearest‐neighbour Te pairs are found to decrease strongly with increasing <jats:italic>x</jats:italic>. For <jats:italic>x</jats:italic> ⪆ 0.85 isolated Te cannot bind an exciton and, therefore, in CdSe only Te pairs lead to bound impurity states. The measured relaxation energies and halfwidths of the corresponding emission and excitation bands yield information on the <jats:italic>x</jats:italic>‐dependence of the electron‐phonon interaction for both types of impurities. The experimental results are discussed on the basis of a simple potential‐well model using variational calculations.</jats:p>