To understand the origins of temperature-dependent contributions to the energetics of the reaction process, we compare findings from CFF-AIMD simulations to those from HA (Figure ), which uses critical points of the PES and captures the vibrational entropy and enthalpy based on normal-mode analysis, zero-point vibrational energy (ZPE) effects, and configurational entropy (see Computational Methods). As seen in Table , there is a good agreement in HA results using quantum and classical harmonic approximation for this reaction at the temperatures studied in this work, providing evidence that quantum effects such as ZPE do not substantially affect the comparisons made in this work. ). The largest deviations between the two methods are seen using SC-HA. There is a good agreement between MCS-HA and CFF-AIMD, showing that additional temperature-dependent effects captured by CFF-AIMD can be explained by configurational degeneracy, thermal averaging of multiple adsorbed states, and vibrational entropy of surface atoms.