You are a chemist. Now you are given a description of a molecule. Please generate a molecule that meets the description.
system
The molecule is a phosphorescent emitter, which is phosphorescent and belongs to the organic electroluminescent device, electroluminescent, and organic electroluminescent material classes of molecules. Use the above information to create a molecule.
user
c1ccc2c(c1)c1ccccc1c1cc(-n3c4cccc5c6ccccc6c6cccc3c6c54)ccc21
assistant