# Why Li can't make it's Peroxide when heated with more O2?

Every first group metal reacts with $\ce{O2}$ and makes there monoxide at room temperature.

But it says that $\ce{Li}$ does not make peroxide when heated with more $\ce{O2}$. But other metals in that group do.

Why $\ce{Li}$ can't make it's Peroxide when heated with more $\ce{O2}$?

And if we give the heat continuously with more $\ce{O2, K, Rb, Cs}$ give there Super-oxides. In that time Both $\ce{Li}$ and $\ce{Na}$ do not gives there Super-oxides. What is the reason for it?