Investigation Nonlinear Properties (First and Second Hyperpolarizabilities) of The Nitro-thieno [3,2-b] thiophene -fullerene (C20) Molecule. Baghdad Science Journal, Iraq, Baghdad, v. 21, n. 6, p. 2146, 2024. DOI: 10.21123/bsj.2023.8659. Disponível em: https://bsj.uobaghdad.edu.iq/index.php/BSJ/article/view/8659.. Acesso em: 22 jan. 2025.