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Updated: Feb 26, 2026

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
A new nonempirical tuning scheme with single self-consistent field calculation: Comparison with global and IP-tuned
Manash Protim Borpuzari1, Rahul Kar1
1Department of Chemistry, Dibrugarh University, Dibrugarh, Assam, 786004, India.
Abstract:
System-dependent nonempirical tuning of range-separated functional provides a way to minimize the delocalization error of the system. However, existing nonempirical tuning method requires the computation of several ΔSCF calculations to determine the optimal μ value. In this article, we have defined a scheme to evaluate the optimal μ value with single self-consistent field calculation. Our method is based on the evaluation of the spherically symmetric average Electron localization function (ELF) region. According to this scheme, the radius of the spherically symmetric average ELF region gives is a measure of the distance at which the long-range part of the range-separated functional becomes dominant. Numerical results indicate that our method improves the reproduction of HOMO energies and HOMO-LUMO gap in comparison to global and IP-tuned range-separated functional. Moreover, in case of HOMO energies, maximum error of the ELF-tuned functional is considerably smaller than the global and IP-tuned functional. Furthermore, our method gives considerably smaller deviation of HOMO energies from ΔSCF IP than global range-separated functional. © 2017 Wiley Periodicals, Inc.
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