jjgoings / McMurchie-Davidson

do a simple closed shell Hartree-Fock using McMurchie-Davidson to compute integrals
BSD 3-Clause "New" or "Revised" License
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Question: Does the ERI routine require that E and R routines both be computed using Hermite Integrals? #22

Closed HemanthHaridas closed 2 years ago

HemanthHaridas commented 2 years ago

I am trying to write a small HF code that can perform energy calculations on molecules (inspired by your excellent blog and this repository). However, I am presently calculating the overlaps via iteration (as explained in https://www.mathematica-journal.com/2012/02/16/evaluation-of-gaussian-molecular-integrals/). I found the other integral schemes (HGP and OS) to be pretty confusing, while MD algorithm is relatively straightforward. My query is regarding the calculation of ERI integrals, where both overlaps and repulsion integrals are calculated. Can I use the unnormalized overlaps calculated from iteration in conjunction with the recursive calculation of RI?

Thanks Hemanth