COMPARISON OF POSITIVE FLUX OPERATORS FOR TRANSITION-STATE THEORY USING A SOLVABLE MODEL

Several quantum operators representing ''positive flux'' are compared for the square barrier by examining their ability to reproduce the exa ct transmittance when traced with the exact microcanonical density ope rator. They are obtained by means of the ''Weyl rule,'' the ''Rivier r ule,'' by symmetrizing the product of ''flux'' and ''positive momentum projection'' operators, acid by a variational technique. Explicit exp ressions are given for all cases. (C) 1996 American Institute of Physi cs.