This award supports collaboration in astrochemistry between Professors William M. Irvine, Paul F. Goldsmith, and F. Peter Schloerb, of the University of Massachusetts; and Professor Shuji Saito, Nagoya University, Japan, as well as other Japanese investigators at Nagoya University, Toyama University, and the Nobeyama Radio Observatory. The researchers will cooperate in several studies aimed at increasing understanding of the chemical composition and processes in interstellar molecular clouds, using the techniques of high-frequency radio astronomy and modern laboratory molecular spectroscopy. The laboratory work will be carried out primarily in the Department of Astrophysics at the University of Nagoya, while astronomical observations will be made at the Five College Radio Astronomy Observatory (FCRAO), which is operated by the University of Massachusetts, and at the Nobeyama Radio Observatory. Chemistry plays an increasingly well-recognized role in the study of important astronomical environments, including the interstellar molecular clouds where stars are believed to form, the envelopes expelled by both young and evolved stars, and cometary comae. In this project, the strengths of three research facilities are brought together, one in the U.S. and two in Japan. Both the U.S. and Japanese investigators bring significant experience and expertise in astrochemistry to this effort. The 14-meter diameter radio telescope of the FCRAO is the largest single-dish millimeter wavelength telescope in North America. Used in conjunction with various state-of-the-art receivers developed at FCRAO, it provides extremely high sensitivity in several spectral frequency regions of interest in these studies. The 45-meter radio telescope at Nobeyama is the largest radio telescope in the world for observations at millimeter wavelengths, and so offers the highest resolution at these wavelengths available with any single dish antenna. Members of the Molecular Spectroscopy Group in the Department of Astrophysics at Nagoya are among world leaders in the laboratory study of highly reactive, unstable molecular species. Cooperation among these three groups has existed for several years, and this award will permit the collaboration to be strengthened and expanded. Specific projects proposed for study include spectral surveys of cold, quiescent interstellar clouds to better determine their chemical composition, investigations of possible molecular formation or equilibration on interstellar grains, studies of the degree of chemical saturation in different environments, and determination of the relative abundance of closely related molecular species in order to investigate reaction pathways.