You should have a resistor in series with an inductor to model the bondwire and a resistor in series to a capacitor to model the pad.

C depends on the pad area and distance to substrate (ie which metal layer is at the bottom of the pad metal stack)
R depends on your process and layout. The process parameters needed are things like substate resistivity etc. Layout effects like where you put sub contacts will also matter. You can uses tools like ASITIC or other extraction tools to help you evaluate it.