Point defect calculations were performed using the standard supercell approach. A 2 × 2 × 1 supercell of Y 2 Te 3 containing 80 atoms was considered. The pylada-defects software was used to automate the point defect calculations. Vacancies and antisite defects in charge states ranging between q = -3 and q = +3 were considered. Additional charge states were considered where necessary e.g., Y Te in q = +4. The ion positions in defect supercells were relaxed using a 4 × 4 × 4 Γ-centered k-point mesh. The formation energy (∆E D,q ) of a point defect D in charge state q was calculated according to the equation