Tailoring of energy levels in lead chloride based layered perovskites and energy transfer between the organic and inorganic planes

Excitonic inter-layer energy transfer is proved in a system consisting of b imolecular layers of organic dyes (benzyl, naphthyl, or anthryl) in lead ch loride perovskites. By a systematic variation of the dye molecules we place the inorganic exciton band of lead chloride energetically beneath, above o r between the singlet and triplet levels of the dye. Therefore we observe e mission from that exciton band, the molecular singlet or triplet level due to energy transfer between the inorganic and organic layers. In the case of the layered perovskite (C6H5-CH2-NH3)(2)PbCl4 we succeeded in energeticall y matching the inorganic exciton band with the molecular triplet level. (C) 1999 Elsevier Science B.V. All rights reserved.