Toward linear scaling: Locality of potential energy surface coupling in valence coordinates

Abstract

We investigate the possible locality of potential energy surface (PES) coupling in curvilinear internal valence coordinates using pure electronic energy as well as vibrational energy guided definitions of PES coupling range on the example of the floppy but‐enal and the semirigid but‐dienol molecule C4OH6. We propose ways to exploit found coupling range limits for efficient PES generation leading to significant computational savings. The generation of the 27 dimensional PESs using vibrationally guided convergence criteria within an adaptive PES generation method (AGAPES) at B3LYP quality is reported as well with a detailed error‐gain analysis. © 2014 Wiley Periodicals, Inc.