Coupling in quantum dot molecular hetero-assemblies

•Molecular assemblies of quantum dots (QD) are prepared in solution, linked by dithiols.•The interparticle distances are tuned by varying the linear alkyl chain length of the dithiols from nanometer to sub-nanometer range.•The crystallographic analysis highlights that the (101) faces of the QDs play an important role in the linkage.•The hetero-assemblies are spectroscopically investigated in solution and compared with the homolog homo-assemblies.•QD coupling is governed by the interparticle distance, the QD size, and the mutual energetic levels arrangement.