PNNL

Abstract

In computational quantum chemistry, the basis set is a fundamental input to many types of simulations, and the choice of basis set can have dramatic effects on both the accuracy and performance of the simulation. Due to this fundamental nature, basis sets have been developed starting at the beginning of the computational chemistry field, and extending to the present day, with new basis sets taking into account new theories and methods now accessible due to increases in computing power. Practically, computations are most comparable when they use the same basis set. However, early distribution channels often led to differing incorporation of basis sets indifferent computational chemistry codes, harming reproducibility and introducing errors in calculations that can go unnoticed. Such errors can be due to many causes, including transcription errors, neglecting publication of the full precision of numerical values, updated values not being incorporated in a timely manner, or development of an ‘improved’ version by different developers that retains the same name as the original basis set. Therefore, there was a need to store basis sets in a central location and make them easily and freely accessible by any researcher. The Basis Set Exchange (BSE) is widely considered by the field to be such a resource.