If you want to reconnect with those from #ChemTwitter who have created accounts here in the #Fediverse, here is a Google Sheet that >400 people have added themselves to.
https://docs.google.com/spreadsheets/d/1qdJvHHvu-BC4N6nk1jNMhTwoBrIaqHLUCZRf9pCQwDs/edit?usp=sharing
If you want to add your details, you need to either fill in this Google Form: https://forms.gle/gF9MLUGMWs23EFix6 or just ask me to add your details if you'd rather not use a Google product (note: the form does not capture e-mail addresses).