What is macleren atom?

There is no such thing as a "macleren atom." It is possible that you meant to ask about the McLaren atom, which is actually a fictional element in video games and manga/anime series. The McLaren atom was first introduced in the game Final Fantasy VII, where it was described as a powerful and very rare materia that could be used to cast a variety of spells and abilities. In other games and series, it has been portrayed as a substance with incredible energy potential, sometimes even capable of creating entire worlds or destroying them. However, it is important to note that the McLaren atom is purely a work of fiction and has no basis in real science or chemistry.