〈Δ𝜃 𝑘 Δ𝜃 𝑙 〉 = 〈Δ𝜃 𝑘 〉〈Δ𝜃 𝑙 〉 = 0 (10) In Eq. 9, Δ𝜃 𝑘 is an unknown time-dependent variable which can either be determined explicitly by nuclear dynamics studies or its moments (mean, standard deviation etc.) can be calculated by molecular dynamics calculations of corresponding polymer. However, for rapid screening of high charge-carrier mobility organic polymers, which is the primary goal of the present work, it will be computationally expensive. Therefore, we approximate the possible value of 〈𝛥𝜃 𝑘 2 〉 and reformulate Eq. 8 considering the average of squared electronic coupling between the electronic states |𝑖⟩ and |𝑗⟩. In that case, the new expression for hopping rate will be, (12).