Efficient method to calculate the electron–phonon coupling constant and superconducting transition temperature

We show an efficient way to compute the electron–phonon coupling constant, λ, and the superconducting transition temperature, T_c from first-principles calculations. This approach gives rapid convergence of T_c with respect to the size of the k-point mesh, and is seamlessly connected to the formulation used in large molecular systems such as alkali fullerides where momentum dependence can be neglected. Since the phonon and electron–phonon calculations are time consuming particularly in complicated systems, the present approach will strongly reduce the computational cost, which facilitates high-throughput superconducting material design.