Property-oriented basis sets for computation of atomization energies.

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Theoretical Chemistry

Background:

• The accurate calculation of atomization energies for organic molecules is crucial in computational chemistry.
• Existing simplified box orbital (SBO) basis sets require optimization for improved performance.
• High-level basis sets like cc-pV5Z provide benchmark accuracy but are computationally expensive.

Purpose of the Study:

• To modify and enhance the SBO4-DZ(d,p)-3G basis sets for superior atomization energy calculations.
• To investigate the impact of adding a second D shell to the SBO basis sets.
• To optimize SBO basis sets for various quantum chemical methods, including Hartree-Fock (HF), Density Functional Theory (DFT), and Møller-Plesset perturbation theory (MP2).

Main Methods:

• Modification of the SBO4-DZ(d,p)-3G basis sets by incorporating an additional D shell.
• Determination of the optimal scale factor for the new D shell by minimizing total energies.
• Further refinement of the scale factor by directly optimizing atomization energies.
• Optimization of simplified box orbital (SBO) basis sets for HF, DFTs, and MP2 methods.

Main Results:

• The addition of a second D shell significantly improved the performance of the SBO basis sets.
• Optimizing the scale factor for atomization energies yielded results comparable to the cc-pV5Z basis sets.
• Tailored SBO basis sets were successfully developed for HF, DFTs, and MP2 calculations.

Conclusions:

• The enhanced SBO basis sets offer a computationally efficient and accurate alternative for calculating atomization energies of organic molecules.
• The developed SBO basis sets provide reliable results across different quantum chemical methodologies.
• These optimized basis sets represent a valuable tool for theoretical studies in organic chemistry.