On the uniqueness of t->0+ quantum transition-state theory

Timothy J. H. Hele; Stuart C. Althorpe

doi:10.1063/1.4819077

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arXiv · 1307.8035

On the uniqueness of t->0+ quantum transition-state theory

Timothy J. H. Hele·Stuart C. Althorpe

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Abstract

It was shown recently that there exists a true quantum transition-state theory (QTST) corresponding to the t->0+ limit of a (new form of) quantum flux-side time-correlation function. Remarkably, this QTST is identical to ring-polymer molecular dynamics (RPMD) TST. Here we provide evidence which suggests very strongly that this QTST (= RPMD-TST) is unique, in the sense that the t->0+ limit of any other flux-side time-correlation function gives either non-positive-definite quantum statistics or zero. We introduce a generalized flux-side time-correlation function which includes all other (known) flux-side time-correlation functions as special limiting cases. We find that the only non-zero t->0+ limit of this function that contains positive-definite quantum statistics is RPMD-TST.

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Timothy J. H. Hele, Stuart C. Althorpe. 2013-07-30. On the uniqueness of t->0+ quantum transition-state theory. https://doi.org/10.1063/1.4819077

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