2.8. Acronyms

The following acronyms are often used in the source code (and the documentation).

These acronyms will often occur in lower case due to coding conventions. When a class represents just one of these terms, longer names may be used for the sake of clarity. Unit conversion constants are not abbreviated.

• AP1roG – Antisymmetric Product of 1-reference orbital Geminal
• DM – Density Matrix
• DFT – Density Functional Theory
• ER – Electron repulsion
• GDB – Gaussian Density Basis
• GOB – Gaussian Orbital Basis
• GPT – Gaussian Product Theorem
• HF – Hartree Fock
• KIN – Kinetic Energy
• LF – Linear Algebra Factory, i.e. class that bundles a set of related linear algebra routines.
• MP2 – 2-nd order Moller-Plesset perturbation theory
• NA – Nuclear Attraction
• OLP – Overlap
• SQ (as suffix, e.g. dist_sq) – Squared
• WFN – Wave Function