A robust approach to calculate entropy change based on density functional theory in the energy representation.

We have developed a new approach to accurately calculate entropy change based on density functional theory in the energy representation. The entropy change was evaluated using the derived equation and energy distributions computed using molecular simulation and reweighting techniques. This approach was applied to a harmonic oscillator, an alanine dipeptide, and a small protein. We found that the results were accurate compared to conventional approaches, such as the quasiharmonic approximation.