I am interested in learning how to do DFT+U calculations and was wondering if anyone has any good recommendations for books or articles.
I recommend this as a go-to source now. We have discussed DFT+U quite a bit on this very site: GO.
Most modern books that cover DFT now cover DFT+U as well, as I believe to be the case in David Singh's book.
Really though, you absolutely need to check out Kevin J.M.'s answer, it is extremely helpful, organized and gives the most relevant resrouces (Cococcioni, Marzari and other giants' works).
Hopefully this gets the ball rolling!
$\begingroup$ I think if you want to study the DFT+U framework from the ground up, the best resources are the seminal papers, most of them are linked in Kevin J.M's answers. Textbooks more often than not go into the Hubbard model, a popular topic in condensed matter. But the original published papers should be more useful, in my opinion. $\endgroup$– Xivi76Dec 17, 2020 at 7:27
$\begingroup$ Thanks to everyone - Etienne Palos, Xivi76, and Nike Dattani. I really appreciate the responses. This is such a great community $\endgroup$ Dec 17, 2020 at 20:05