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As @anyon suggested, I contacted Larry directly. He also directed me to using the archive.org versions of the databases. As soon as I have the time, I'll try to add the databases into an up-to-date da …

Relativistic correlation methods are another interesting topic: usually one employs the no-pair approximation, which doesn't correlate the negative energy states. However, there's really no reason why …

That's an okay toy project, but you shouldn't expect too much from it. Dozens (or hundreds!) of functionals have been fit to experimental data over several decades with varying success. You didn't spe …

There's two later review articles by Schollwöck that weren't in Nike's excellent list: 2011: Phil. Trans. R. Soc. A (2011) 369, 2643–2661 2011: Annals of Physics 326 (2011) 96–192

The question was about "orbital basis sets" but explicitly mentions Gaussians; I guess the topic here is atomic orbital basis sets. In this case, the molecular orbitals are expanded as a linear combin …

You don't have to write special code for derivative integrals. Since you know that the Cartesian Gaussian basis functions are of the form $ \chi_x = (x-x_0)^l \exp[-\alpha (x-x_0)^2]$ (same for the ot …

I think there are none. If you look at e.g. the work by Dunning, the problem is that the functions appear in a semi-random order: e.g. the second D function may be energetically more important than th …

This is a question that is answered by a straightforward literature search, here's e.g. two review papers from the 1980s: J. Chem. Inf. Comput. Sci. 25, 334 (1985) J. Chem. Educ. 65, 574 (1988) as w …

Typically, force evaluation happens in Cartesian coordinates regardless of the approach (QM or MM). In QM codes the forces may then be projected into internal coordinates, which in turn is usually dep …

The paragraph on Wikipedia you are citing reads in full Two different physical explanations have been given[5] for the increased stability of high multiplicity states. In the early days of quantum me …

A good place to start is the classical Allen-Tildesley book, Computer Simulation of Liquids, which covers the basics of molecular dynamics that hasn't really changed in a long time. The book can be su …

A general rule of thumb: never trust results obtained with only one functional (or basis set). If two different functionals give you a similar result, then you can trust the results. If the prediction …

Molecular integrals aren't typically computed in spherical harmonics. What you do instead is to compute the integrals in the Cartesian representation, where they are separable, and then transform to t …

As Ian Bush already pointed out in a comment above, the work by Pisani et al on the Gaussian basis implementation the CRYSTAL program is the original reference for periodic Hartree-Fock. More recently …

The general answer is: no. Take the total spin, $\hat{\bf S}^2$, for example. Although quantum chemistry programs typically compute the expectation value $\langle \hat{\bf S}^2 \rangle$ using the non- …