Peter Pulay of the University of Arkansas is supported by an award from the Theoretical and Computational Chemistry program within the Division of Chemistry to carry out research on developing efficient methods for electronic structure calculations of large systems. Pulay is using a combination of gaussian and plane-wave basis functions to allow calculations on large molecules such as those of interest in molecular biology. He is also developing a Fourier Transform Coulomb (FTC) method that is expected to increase the efficiency of his density functional theory (DFT) program by about two orders of magnitude, which would remove a major bottleneck in the existing code. A second project involves the development of a new Coupled Cluster (CC) code that is expected to be about ten times faster than currently available methods. The codes resulting from this research will be distributed to other researchers and are expected to have a major impact on simulations of interest in fields such as materials science, molecular biology and nanotechnology.