I am an assistant professor of chemistry. My department strongly values international collaborations. I contacted some research groups working on the same topics as mine, but half of them wanted my fund, and the other half thought I want theirs.
My imagination of research collaboration was that two groups do parts of a research idea by their available funds, and then preparing a joint paper by combining the results.
For example, a common suggestion I received is that they can host a PhD student or a postdoc fellow (for a minimum period of one year for the sake of official paperwork and adaptability) if I have a fund. How can I fund someone to work somewhere else on a project different from my funded project? And how is it a collaboration after all?
In my experience, it is very difficult to spend research funds in another country. It is even impractical to send joint proposals (unless there are governmental agreements between two countries). I wonder how do researchers from various countries plan international collaborations (which is apparently very common based on the joint papers)?