van-der-waals maybe could be switched to "long-range-interactions" this includes "dispersion", "van der waals", "LeRoy-Bernstein" and others.
I agree about make tags for MOLPRO, Q-Chem, VASP, Amber, etc. In fact, let's make those tags in advance, because when tags don't exist, people make their own tags, and sometimes they don't have experience with SE and they don't make the most fitting tag names. If the tags are already there, then they can select from something that exists.
@user1271772 You cannot make tags in advance. Tags only exist, iff they are attached to a question. And I believe during beta, they must reach a threshold of 6 to not be cleared by the system; but this could have changed.
Also, from experience, having tags there will help, but it won't deter the determined from creating new tags with weird names...
@Martin-マーチン Yes, I just saw it. I tried to make a synonym (are we allowed?), but I ended up editing all questions under [dft] to use [density-functional-theory].