Here is my first post-Flash work.
Derek Keller is a former student of the Institute turned teacher who can manipulate the atomic structure of everything around him. As such, he fought crime as Periodic. He is the chemistry teacher and a favorite amongst the students. His flashy demonstrations and fun easygoing nature have won him many friends.
This is a sharp contrast to him as a student, where he was more of a introverted nerd type. His experiences and friends, especially his best friend Eric Hayes, brought him out of his shell however.