Evaluating Noncovalent Interactions in Halogenated Molecules with Double-Hybrid Functionals and a Dedicated Small...

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Materials Science

Background:

• Accurate calculation of interaction energies in weakly interacting halogenated molecules is crucial for understanding chemical processes.
• Existing methods often require large basis sets and empirical corrections, increasing computational cost.

Purpose of the Study:

• To extend the PBE-QIDH/DH-SVPD basis set to halogen atoms (F, Cl, Br, I).
• To achieve interaction energies comparable to high-level methods for halogenated molecules.

Main Methods:

• Developed a self-consistent split-valence basis set (DH-SVPD) for halogen atoms.
• Tested the new basis set on standard benchmarks (X40, X4 × 10) and other datasets.
• Evaluated performance on a large molecular system (380 atoms).

Main Results:

• The PBE-QIDH/DH-SVPD approach accurately predicts interaction energies for various halogenated systems.
• The method demonstrates reliability across different data sets and system sizes.
• Results are comparable to more computationally expensive methods.

Conclusions:

• The PBE-QIDH/DH-SVPD method provides a simple, nonempirical, and accurate way to compute interaction energies.
• It serves as a cost-effective alternative to double-hybrid functionals with empirical dispersion and large basis sets.
• This advancement facilitates more accessible computational studies of halogenated molecules.