# What's an acceptable computation chemistry question?

Both the "Tour" page and the "Asking" page indicate that computational questions are off-topic, but there is a computational tag, and such questions are rarely closed as off-topic.

What constitutes an on- or off-topic computational question? Can that clarification be added to the help pages?

• I'm not so sure what you're talking about. There are some cases when question about computational chemistry may be off topic. One of the reasons is mentioned - when question is rather about workings of numerical method. There are other ones, like "why my script doesn't work", or "which method is better". I don't think all reasons why question may get closed are possible to list in tour or help. – Mithoron Jan 12 '20 at 19:25
• This isn't really the correct place to debate this, but I think "which method is better" (in the sense of, e.g., which DFT functional is better for a certain system) can be fully on-topic. Such comparisons are published regularly in JCTC and other journals. – orthocresol Jan 13 '20 at 1:04
• There is a discussion about this topic and there is quite a lot support for CC questions: chemistry.meta.stackexchange.com/q/3425/4945 I don't think we have gotten around to actually write up guidelines, or even editing the mentioned pages; but that was on the to-do list for a few days (years) now. – Martin - マーチン Jan 13 '20 at 1:05
• Btw, I am happy to help with drafting some guidelines; but I think I need to be clear about what the guidelines should be first... – orthocresol Jan 13 '20 at 1:13
• @orthocresol and OP All this does not say some type of question is completely banned! I have a feeling OP has some issues against brevity, or maybe lacking context... – Mithoron Jan 13 '20 at 16:26
• @Mithoron, I'm not sure how you interpret the tour wording of "Don't ask about: [...] computational questions", but I think the meaning is quite clear. It means that computational questions are not welcome here. – orthocresol Jan 13 '20 at 16:28
• sigh then remove it or reword it. But really all these points in tour are so oblique to newbies that I doubt it could be helped. Seriously, I wouldn't be surprised if there are guys that don't really get all this "Homework" after a year, or two, or never. – Mithoron Jan 13 '20 at 16:41

What constitutes an on- or off-topic computational question?

We might unwittingly be reopening a can of worms here... I am not sure if there is (100%) clear consensus on what is on- and off-topic here. And I am not sure if there are enough active users who care about such questions to form a consensus.

It is pretty clear that "find the typos in my input file"-type debugging questions, or "how do I install this software" questions, are generally considered off-topic. On the other hand, questions more about the theory behind the calculations are also obviously on-topic. The main problem is that there is a grey area in the middle, with things such as (quoting) "How do I set up a geometry optimisation in Gaussian?". Some don't like it, some do. There are very valid arguments for both sides.

The accepted answer, though, seems to suggest that (at least in 2016) the policy is to allow questions in the gray area. So I guess it is fair to say that even though not everybody agrees with it, there is some kind of consensus, as judged by the votes (and green tick). I would prefer having a second opinion on this though...

Can that clarification be added to the help pages?

In my opinion that the first step is not to modify the help pages, but rather to make a FAQ-style post on Meta, describing what sort of questions are on- or off-topic, and why. (The post linked above isn't particularly helpful for a new visitor - it has a lot of back-and-forth, and is probably too confusing to read.)

Once that's done, then the help page can (and should) be updated with a link to this post. I don't think it's possible to summarise the entire discussion within the help page itself.

• One simple step might be to remove "computational questions" from the "Don't ask." portion of the Tour page and only mention them in the slightly more detailed Asking page. I also wonder if historically the intent was to forbid questions about simple calculations like "how many grams are in 3 moles of methane?". If those questions are what is meant, perhaps "don't ask about. . . checking your specific calculation" might be better wording, as "calculation" and "computation" are generally used slightly differently by chemists. Subtle, though. – Andrew Jan 13 '20 at 12:54
• In general, the tour and help pages are ancient and have not been substantially revised for at least a few years. I think most of the (customisable) text there predates me (I joined in 2015). – orthocresol Jan 13 '20 at 13:02
• For what it's worth, I've already removed the line from the Tour page; after all, the computational questions that we don't like generally fall under the banner of "questions not directly related to chemistry". – orthocresol Jan 18 '20 at 19:14
• $+1$ Great Ortho ;) – user8718165 Jan 23 '20 at 11:08
• At the time I asked the linked question, the intention was to write a faq style follow up post. I never got around to it, and it seemed less and less important. Since it came up again, it might be worthwhile restarting the effort. – Martin - マーチン Jan 24 '20 at 14:43

The Tour page says don't ask "Computational questions". It also says don't ask "Anything not directly related to chemistry". It does not say don't ask about "Computational chemistry".

For example, if I want to get the total mass of a solution where 5.0 g of sodium chloride dissolved in 200.0 g of water, and I already know I have to add the two masses, but don't know how, that question would be a bad fit. First, because it is a computational question, and second, because it is not directly related to chemistry.

I would think that "Anything not directly related to chemistry" is sufficient for the tour, and "Computational questions" could be dropped. There might be places elsewhere for collecting the most annoying types of question that are bad and keep coming up. I would suspect that these would change over time. For example, it might have been a problem to solve a cubic equation numerically in the past, but now people just use Wolfram Alpha or a similar tool to get the answer.

• There is a difference between a "calculation" and a "computation". The mass of the solution example you give is a calculation. – LordStryker Jan 21 '20 at 20:55
• @LordStryker english.stackexchange.com/questions/10316/… ... potato potato? – Karsten Theis Jan 23 '20 at 23:20
• It is not as trivial as it seems for people in the field. Besides, in a conversation regarding acceptable "computational chemistry" questions, a distinguishable line between calculation and computation is useful and perhaps necessary. – LordStryker Jan 23 '20 at 23:57