Molionic Lattices. The Organic Semiconductors Tmpd/CLO4 and Tmpd/Chloranil

摘要

By the techniques of ultraviolet spectroscopy, electron spin resonance, X-ray diffraction, differential thermal analysis and the measurement of the electronic conductivity it was shown that the lattice of the donor-acceptor complex N-N-N'-N'-tetra-methyl-p-phenylenediamine (TMPD) Chloranil (CA) consists of molecules in a super-lattice of the bipositive and binegative ions (TMPD(++) and CA(=) of the constituting species. Similarly, the low temperature phase of Wurster's Blue Perchlorate consists of alternating bipositive ions and neutral molecules of TMPD. This intimate mixing of molecules and ions explains all of the measured properties of the substances, such as their paramagnetism, their electrical conductivity and their ultraviolet and visible absorption spectra. The theoretical considerations put forward appear to offer a way of interpreting similar properties in a large number of other organic semi-conductors. (Author)