JuliaCon 2025

In quantum chemistry, Gaussian basis sets are essential for approximating molecular wavefunctions, where a complete basis set represents an infinite set of functions approaching the exact solution of the Schrödinger equation. Achieving completeness in these basis sets is crucial for high-precision molecular modeling and simulations. However, this completeness is often limited by practical computational constraints, making optimization a key step in enhancing the accuracy of quantum chemical calculations.

The BasisSets.jl package in Julia addresses this challenge by leveraging the language's high-performance computing and advanced AD features. Julia’s efficient handling of AD is particularly advantageous for optimizing basis sets, enabling automatic and precise calculation of derivatives, a vital component in this optimization process.

This talk will provide an insightful overview of what constitutes a complete basis set and the significance of its optimization in quantum chemistry. We will demonstrate how BasisSets.jl facilitates this optimization, leading to more accurate and computationally efficient quantum chemical calculations. The ability to optimize Gaussian basis sets to near-completeness has profound implications for molecular dynamics, material science, and drug design, where precise molecular modeling is paramount.

Attendees will gain an understanding of the challenges in achieving complete basis sets, the role of Julia and BasisSets.jl in overcoming these challenges, and how this optimization enhances the capabilities of quantum chemistry. The session will feature practical examples, showcasing the application and impact of optimized basis sets in real-world quantum chemical problems, by exploring the BasisSets.jl package, another implementation within the HartreeFoca organization, focused on open source for modern electronic structure methods.