Three low molecular weight model compounds for poly(phenylene-ethynylene)s were inserted into the channelsof zeolite L by using gas phase insertion. The absorption and emission spectra in solution and dye/zeolite Lare reported. Two compounds show emission properties in zeolite L comparable to that in solution. In contrast,the bipyridine containing compound shows a red shift toward longer excitation wavelengths. Matrix rankanalysis of the emission spectra gave three contributing species. Quantum chemical calculations provide differentconformations depending on the Si/Al distribution of the framework and the extraframework cations andattached protons.