I've been searching for a while, but I haven't found anything about this. Basically, a lot of gasious elements in TPT don't have liqued and solid forms, nor do many liqueds have solid forms, which doesn't make sense as they should be solid at 0 k. I think that it would greatly improve the gameplay if everything was frozen at absolute zero.
Ok, where do I go if I want to find it as a mod then?
You will not be able to find this as a mod to my knowledge, though it might be somewhere. I don't think it's a problem that TPT isn't realistic in this way. It would break a lot of saves as just mentioned. I would recommend checking out every mod you can find (in the forum and wiki, there's a list there), but you'll probably have to make it yourself. It's likely it doesn't exist yet, and if it doesn't it's not likely to be made.