need for molecular dynamics has demonstrated capability for accurate prediction of anharmonic free energy and phase transition across strongly anharmonic materials from shape-memory alloys to the materials presented in this paper . This method uses about 3 ∼ 4 orders of magnitude less computation time than TI performed with AIMD. If properly implemented, TI by design offers a complete description of anharmonic free energy whether or not a system is dynamically unstable by accounting for the actual potential difference between a temperaturedependent harmonic potential and the actual potential (or an approximation thereof). Though it would add to the computational expense beyond the essentially instantaneously calculable correction formula we adopt here, its computational demand is still within high-throughput applicability.