title: Substituent effects on the optical properties of naphthalenediimides: A frontier orbital analysis across the periodic table.
abstract: A comprehensive theoretical treatment is presented for the electronic excitation spectra of ca. 50 different mono-, di-, and tetrasubstituted naphthalenediimides (NDI) using time-dependent density functional theory (TDDFT) at ZORA-CAM-B3LYP/TZ2P//ZORA-BP86/TZ2P with COSMO for simulating the effect of dichloromethane (DCM) solution. The substituents -XHn are from groups 14-17 and rows 2-5 of the periodic table. The lowest dipole-allowed singlet excitation (S0 -S1 ) of the monosubstituted NDIs can be tuned from 3.39 eV for -F to 2.42 eV for -TeH, while the S0 -S2 transition is less sensitive to substitution with energies ranging between 3.67 eV for -CH3 and 3.44 eV for -SbH2 . In the case of NDIs with group-15 and -16 substituents, the optical transitions strongly depend on the extent to which -XHn is planar or pyramidal as well as on the possible formation of intramolecular hydrogen bonds. The accumulative effect of double and quadruple substitution leads in general to increasing bathochromic shifts, but the increased steric hindrance in tetrasubstituted NDIs can lead to deformations that diminish the effectiveness of the substituents. Detailed analyses of the Kohn-Sham orbital electronic structure in monosubstituted NDIs reveal the mesomeric destabilization of the HOMO as the primary cause of the bathochromic shift of the S0-S1 transition.
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, VU University Amsterdam, De Boelelaan 1083, Amsterdam, 1081 HV, the Netherlands.|Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling (ACMM), VU University Amsterdam, De Boelelaan 1083, Amsterdam, 1081, HV, the Netherlands.
authors.forename: Joshua R
authors.initials: JR
authors.lastname: Mulder
authors.affiliation: Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling (ACMM), VU University Amsterdam, De Boelelaan 1083, Amsterdam, 1081, HV, the Netherlands.
authors.forename: Célia Fonseca
authors.initials: CF
authors.lastname: Guerra
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, VU University Amsterdam, De Boelelaan 1083, Amsterdam, 1081 HV, the Netherlands.
authors.forename: J Chris
authors.initials: JC
authors.lastname: Slootweg
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, VU University Amsterdam, De Boelelaan 1083, Amsterdam, 1081 HV, the Netherlands.|Department of Chemistry, University of Johannesburg, Auckland Pk Kingsway Campus, Auckland Pk, ZA-, 2006, South Africa.
authors.forename: Koop
authors.initials: K
authors.lastname: Lammertsma
authors.affiliation: Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling (ACMM), VU University Amsterdam, De Boelelaan 1083, Amsterdam, 1081, HV, the Netherlands.|Institute of Molecules and Materials (IMM), Radboud University Nijmegen, Heyendaalseweg 135, Nijmegen, 6525 AJ, the Netherlands.
authors.forename: F Matthias
authors.initials: FM
authors.lastname: Bickelhaupt
mesh_terms: D006860:Hydrogen Bonding; D007094:Imides / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009281:Naphthalenes / Q000737:chemistry*; D010777:Photochemistry; D011789:Quantum Theory
chemical_list: D007094:Imides; D009281:Naphthalenes; C542131:naphthalenediimide
keywords: electronic excitations; long-range corrected functional; naphthalene diimides; orbital electronic structure; time-dependent density functional theory