f-electrons in chemistry of heavy transition metals
&quot;f-hole is critical to describe DoS of IrO2 correctly.&quot;


[...]


This implies, that f-electrons are somewhat involved into chemistry of Ir.

Perhaps naïvely, but I would dispute that the second statement follows from the first. While f-electrons are generally not critical for the chemical reactivity of molecules or materials, their inclusion indeed is critical for a proper description of the Density of States. The magnetic and optical properties, notably, can be derived from the DoS and depend directly from f electrons.