THE PREDICTION OF THE STRUCTURE OF TECHNETIUM(V) COMPLEXES USING DENSITY-FUNCTIONAL TECHNIQUES

Electronic structure calculations using the local density functional m ethod were shown to accurately reproduce the geometry of five oxo-Tc(V )-based radiopharmaceuticals containing a variety of donor ligands. Ca lculations were performed using the DGauss program on a Gray C90 super computer, requiring approximately 40 CPU h for each molecule. The pred icted bond lengths were within +/-0.04 Angstrom of the crystallographi c coordinates, and bond angles within +/-4 degrees, Root mean square ( RMS) deviations between the predicted and crystallographic coordinates were less than 0.06, and visual inspection demonstrated nearly perfec tly superimposible structures. (C) 1997 Elsevier Science Inc.