Linear and nonlinear optical properties of nucleic acid bases

► Electronic and vibrational (hyper)polarizabilities of nucleobases were computed. ► We used HF, MPn, CCSD and DFT levels of calculation with the aug-cc-pVDZ basis set. ► Solvation effects were evaluated under the PCM approximation. ► The OKE, IDRI, EFISHG and THG NLO processes were investigated at λ = 1064 nm. ► The CAM-B3LYP functional furnishes satisfactory (hyper)polarizability predictions.