The partition function Z for a system is given by: \[ Z = \sum_{i} e^{-E_i/k_BT} \] For a complex catalytic system, the partition function can be decomposed into translational, rotational, vibrational, and electronic contributions. Each of these components can be calculated separately and then combined to give the total partition function: \[ Z_{total} = Z_{trans} \cdot Z_{rot} \cdot Z_{vib} \cdot Z_{elec} \]
