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arXiv · 2502.15750

Transferability and interpretability of vibrational normalizing-flow coordinates

Emil Vogt·Álvaro Fernández Corral·Yahya Saleh·Andrey Yachmenev
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Abstract

The choice of vibrational coordinates is crucial for the accuracy, efficiency, and interpretability of molecular vibrational dynamics and spectra calculations. We explore the recently proposed normalizing-flow vibrational coordinates, which are learned molecule-specific coordinate transformations optimized for a given basis set. Much like how spherical coordinates naturally simplify the hydrogen atom by embedding physical insight into the coordinate system, normalizing-flow coordinates offload complexity from the basis functions into the coordinate transformation itself. This shift not only improves basis-set convergence, but also enhances interpretability of vibrational motions. We provide an analysis of the utility, interpretation and associated constraints of normalizing-flow vibrational coordinates. Moreover, we demonstrate that these coordinates can be generalized across different isotopologues, and even structurally related molecules, achieved with minimal fine-tuning of selected output parameters.

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Emil Vogt, Álvaro Fernández Corral, Yahya Saleh, Andrey Yachmenev. 2025-10-27. Transferability and interpretability of vibrational normalizing-flow coordinates. https://doi.org/10.1063/5.0285954

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