Vol.:(0123456789) Optical and Quantum Electronics (2019) 51:332 https://doi.org/10.1007/s11082-019-2047-x 1 3 Designing difuoro substituted benzene ring based fullerene free acceptors for small Naphthalene Di‑Imide based molecules with DFT approaches Usman Ali 1  · Ayesha Javed 2  · Amanullah 2  · Muhammad Shoaib 2  · Muhammad Kashif 2  · Ali Raza 3  · Shi‑Bo Cheng 4  · Javed Iqbal 5 Received: 8 April 2019 / Accepted: 24 September 2019 © Springer Science+Business Media, LLC, part of Springer Nature 2019 Abstract Herein current research work, we designed four new acceptor materials for small solar cell molecules with Naphthalene Di-Imide central unit by employing the wB97xd/6-31 G (d,p) and TD-wB97xd/6-31 G (d,p) level of density functional theories. Absorption properties of designed materials are excellent between the 400 nm to 510 nm with chloroform solvent and 340 nm to 490 nm in gas phase, small reorganization energy values 0.0163–0.0172 eV for electron (λ e ) and 0.0205–0.0257 eV for hole transfer (λ h ), large expected open circuit voltages (V oc ) from 3.60 to 4.53 eV with respect to [6, 6]-phenyl-C61-butyric acid methyl ester (PCBM), high dipole moment strength ranging from 4.0199 to 8.9647 Debye in excited state and 3.3847 Debye to 7.2632 Debye in ground state which are very helpful for the further construction of organic solar cell (OSC) devices with improved and better power conversion efciencies (PCEs). Keywords Frontier molecular orbitals · Di-fouro substituted benzene ring · Absorption bands · % RD · Transition dipole moment Electronic supplementary material The online version of this article (https://doi.org/10.1007/s1108 2-019-2047-x) contains supplementary material, which is available to authorized users. * Usman Ali usmanqureshi320@gmail.com; usmanqureshi320@mails.ucas.ac.cn * Ayesha Javed javedaisha16@gmail.com 1 Key Laboratory of Organic Solids, Institute of Chemistry Chinese Academy of Science, Beijing 100190, People’s Republic of China 2 Department of Chemistry, University of Agriculture, Faisalabad 38040, Pakistan 3 Department of Physics, University of Agriculture, Faisalabad 38040, Pakistan 4 School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People’s Republic of China 5 Punjab Bio-energy Institute, University of Agriculture, Faisalabad 38040, Pakistan