The Electronic Spectra of Diphenylacetylene and 1,3-Butadiyne

The electronic absorption spectra of 2,4-hexadiyne-1,6-diol, diphenylacetylene, and diphenyldiacetylene were measured in a single crystalline state with a polarized light. The results of the polarization measurement and the theoretical calculations gave confirmative assignments of the electronic transitions of these molecules.