I think that you are missing to generate the dictionary of the Molecule class that you are inlining now in the .C class. Move it to a separate header and use Dictionary Example · Modern CMake .
I would strongly suggest to use instead these instructions.
That way, you do not need to generate dictionaries or create CMakeLists, etc. You just select your macro from a dropdown menu, and run it.
This is what I see when running your analysis.C from there. No need for CMakeLists or dictionaries, just out of the box:
