REMOVAL OF THE BOTTLENECK IN LOCAL CORRELATION METHODS

We present preliminary results from a new hybrid pseudospectral local correlation method in which we combine the pseudospectral approximatio n to two-electron integral evaluation with local truncation of the vir tual space to accelerate singles and double excitation configuration i nteraction (SDCI). The combination of the two leads even in small mole cules to overall speed-ups of factors of 3-5 and reduces the main disk space requirement by factors of 9-20 while retaining at least 98% of the correlation energy of the exact SDCI calculations. These prelimina ry results bode well for the advantages of further development of pseu dospectral local correlation methods.