A DATA-STORAGE SYSTEMM based on a new azo compound could increase the memory capacity of future electronic devices. Most electronic memory systems use binary data storage, in which data are recorded as a string of zeros and ones. However, a few ternary systems—mostly experimental—have been developed that record data as zero, one, or two. In principle, the additional value means that a ternary system can hold much more data than a binary system does in a given amount of space within a storage device. Now, Jianmei Lu, Hongwei Gu, and colleagues at Soochow University, in Suzhou, China, have devised a new ternary system ( J. Am. Chem. Soc., DOI: 10.1021/ja910243f). The researchers synthesized the azo compound and sandwiched it between indium tin oxide (ITO) and aluminum electrodes. Each aluminum electrode, along with the small region of the azo material and ITO directly below it, serves as a memory storage unit, akin to the individual magnetized ...