Reducing the complexity of sum-of-products potential energy surfaces for efficient MCTDH calculations
Abstract
The efficiency of the multi-configuration time-dependent Hartree (MCTDH) method depends critically on the availability of a compact sum-of-products (SOP) representation of the potential energy surface (PES). For medium- and high-dimensional molecular systems, conventional SOP representations often contain thousands of product terms, leading to long compilation times, high memory consumption, and prohibitive computational cost. In this work, we introduce a physically motivated factorization procedure that transforms an existing SOP PES into a substantially more compact form without altering the underlying potential. The method is applied to three molecular complexes of increasing dimensionality, reducing the number of SOP terms by 73.8%, 51.7%, and 90.6% for PO+–H2, H2O–HCN, and H2O–H2O, respectively. These reductions translate into substantially lower memory requirements and shorter compilation and propagation times. In every case, vibrational energy levels computed with the factorized PES are in excellent agreement with those obtained from the original SOP representation, demonstrating that the factorization preserves the accuracy of quantum-dynamics calculations while markedly improving computational efficiency. The proposed strategy provides a general and efficient framework for extending MCTDH calculations to increasingly complex molecular systems.
Related
- Reducing QUBO Complexity in Drone Delivery Through Classical Feasibility Preprocessing
- An efficient approach to electron-phonon coupling calculations of heterostructures within an all-electron framework
- AES-Debye: an Accurate, Efficient, and Scalable Engine for Debye Scattering Calculations
- A numerical and efficient model for thermo-field electron emission calculations
- Efficient three-phase Free-Water Flash calculations for water-hydrocarbon mixtures
BibTeX
@article{tela2026reducing,
title = {{Reducing the complexity of sum-of-products potential energy surfaces for efficient MCTDH calculations}},
author = {Hervé Tajouo Tela and Sosthène Irambona and Ayda Badri and Nicola Tasinato and Pascale Chelin and Fabien Gatti and Steve Ndengue},
journal = {Physical Chemistry Chemical Physics},
year = {2026},
month = aug,
doi = {10.1039/d6cp02864k},
url = {https://hal.science/hal-05769821v1},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - JOUR
TI - Reducing the complexity of sum-of-products potential energy surfaces for efficient MCTDH calculations
AU - Hervé Tajouo Tela
AU - Sosthène Irambona
AU - Ayda Badri
AU - Nicola Tasinato
AU - Pascale Chelin
AU - Fabien Gatti
AU - Steve Ndengue
PY - 2026
DA - 2026/08/24
JO - Physical Chemistry Chemical Physics
DO - 10.1039/d6cp02864k
UR - https://hal.science/hal-05769821v1
AB - The efficiency of the multi-configuration time-dependent Hartree (MCTDH) method depends critically on the availability of a compact sum-of-products (SOP) representation of the potential energy surface (PES). For medium- and high-dimensional molecular systems, conventional SOP representations often contain thousands of product terms, leading to long compilation times, high memory consumption, and prohibitive computational cost. In this work, we introduce a physically motivated factorization procedure that transforms an existing SOP PES into a substantially more compact form without altering the underlying potential. The method is applied to three molecular complexes of increasing dimensionality, reducing the number of SOP terms by 73.8%, 51.7%, and 90.6% for PO+–H2, H2O–HCN, and H2O–H2O, respectively. These reductions translate into substantially lower memory requirements and shorter compilation and propagation times. In every case, vibrational energy levels computed with the factorized PES are in excellent agreement with those obtained from the original SOP representation, demonstrating that the factorization preserves the accuracy of quantum-dynamics calculations while markedly improving computational efficiency. The proposed strategy provides a general and efficient framework for extending MCTDH calculations to increasingly complex molecular systems.
SN - 1463-9076
SN - 1463-9084
ER -