Description of two electron integrals with tensor

Two electron integrals is a mathematical entity that describes how two electrons interact with each other. This building block is an important part of the mathematical expressions and computer programs used to express and calculate the wave functions. Using alternative tensor representations, compared with the conventional representation of two electron integrals, one can rewrite expressions and writing computer programs so that they become much more efficient and can handle larger molecular systems. We use Cholesky decomposition to achieve this.