This is one of those advanced topics beyond my course of study of chemistry. But, this resource looks useful for advanced chemistry students. It is a database of basis sets from the Environmental and Molecular Sciences Laboratory at Pacific Northwest National Laboratory. The Basis Set Exchange “provides a web-based user interface for downloading and uploading Gaussian-type (GTO) basis sets, including effective core potentials (ECPs), from the EMSL Basis Set Library. It provides an improved user interface and capabilities over its predecessor, the EMSL Basis Set Order Form, for exploring the contents of the EMSL Basis Set Library. The popular Basis Set Order Form and underlying Basis Set Library were originally developed by Dr. David Feller and have been available from the EMSL webpages since 1994.”

Some basic information on basis sets so that anyone searching The Free Textbook List will find this entry… from Wikipedia . . . A basis set in theoretical and computational chemistry is a set of functions (called basis functions) which are combined in linear combinations (generally as part of a quantum chemical calculation) to create molecular orbitals. For convenience these functions are typically atomic orbitals centered on atoms, but can theoretically be any function; plane waves are frequently used in materials calculations.

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Basis Set Exchange