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RGUceda

Member

Registered: 2023-05-06

Posts: 10

RI approximation

Good afternoon:
My question is very general, but I have not been able to find a detailed and satisfactory answer: what is the RI approach? I have seen that it is used quite a lot, for example, together with CC2, and that it helps in calculation times, but I have not found either by what order of magnitude it speeds up the calculation or a detailed explanation of why it allows faster calculations.
Thanks in advance

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 1,773

Website

Re: RI approximation

RI is a general concept and has different specific use in accelerating different kinds of quantum chemistry methods, including DFT, MP2, CC2, -F12 and so on. Introduction to Computational Chemistry (3ed,Frank Jensen,2017) has a good introduction on RI.