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From Pyridine Adduct of Borabenzene to (In)Finite Graphene Architectures Functionalized with N→B Dative Bonds From Pyridine Adduct of Borabenzene to (in)finite Graphene Architectures Functionalized with N!B Dative Bonds. Prototype Systems of Strong One and Two Photon Quantum Transitions Triggering Large Nonlinear Optical Responses Panaghiotis Karamanis, Nicolás Otero, Demetrios Xenides, Hassan Denawi, Marcos Mandado, Michel Rérat To cite this version: Panaghiotis Karamanis, Nicolás Otero, Demetrios Xenides, Hassan Denawi, Marcos Mandado, et al.. From Pyridine Adduct of Borabenzene to (in)finite Graphene Architectures Functionalized with N!B Dative Bonds. Prototype Systems of Strong One and Two Photon Quantum Transitions Triggering Large Nonlinear Optical Responses. Journal of Physical Chemistry C, American Chemical Society, 2020, 124, pp.21063-21074. 10.1021/acs.jpcc.0c05190. hal-02935781 HAL Id: hal-02935781 https://hal.archives-ouvertes.fr/hal-02935781 Submitted on 14 Dec 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. The Journal of Physical Chemistry This document is confidential and is proprietary to the American Chemical Society and its authors. Do not copy or disclose without written permission. If you have received this item in error, notify the sender and delete all copies. From Pyridine Adduct of Borabenzene to (in)finite Graphene Architectures Functionalized with N→B Dative Bonds. Prototype Systems of Strong One and Two Photon Quantum Transitions Triggering Large Nonlinear Optical Responses Journal: The Journal of Physical Chemistry Manuscript ID jp-2020-05190a.R2 Manuscript Type: Article Date Submitted by the n/a Author: Complete List of Authors: Karamanis, Panaghiotis; Institut des Sciences Analytiques et de Physico- chimie pour l'Environnement et les Materiaux, Otero, Nicolás; University of Vigo - Lagoas Marcosende Campus Xenides, Demetrios; University of Patras Denawi, Hassan; Aix-Marseille Universite, IPREM Mandado, Marcos; Universidade de Vigo, Physical Chemistry Rérat, Michel; IPREM / UPPA, STEE ACS Paragon Plus Environment Page 1 of 44 The Journal of Physical Chemistry 1 2 3 4 5 6 7 From Pyridine Adduct of Borabenzene to (in)finite Graphene Architectures Functionalized with 8 N→B Dative Bonds. Prototype systems of Strong One and Two Photon Quantum Transitions 9 10 Triggering Large Nonlinear Optical Responses. 11 12 13 14 15 16 17 18 19 Panaghiotis Karamanis,*a Nicolás Otero,b Demetrios Xenides,c Hassan Denawi,a Marcos 20 21 Mandadob and Michel Rérata 22 23 24 25 26 27 28 a 29 CNRS/ UNIV Pau & Pays Adour, Institut Des Sciences Analytiques et de Physico-Chimie pour 30 31 l'environnement et les Materiaux –, UMR5254, 64000, Pau, France. Hélioparc Pau Pyrénées 2avenue 32 33 du Président Angot, 64053 PAU Cedex 09 – France. 34 35 b 36 Department of Physical Chemistry, University of Vigo, Lagoas-Marcosende s/n, 36310.Vigo, 37 Spain 38 cDepartment of Chemistry, University of Patras, GR-26500, Greece 39 40 41 42 *corresponding author: [email protected] 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 1 59 60 ACS Paragon Plus Environment The Journal of Physical Chemistry Page 2 of 44 1 2 3 4 5 Abstract. 6 7 The synthesis and optoelectronics properties of polyaromatic hydrocarbons (PAHs) doped with boron and 8 nitrogen units (BN) monopolize the interest of increasing numbers of researchers the past few years. The 9 10 key-concept fueling these attempts lies on the prospect of engineering novel organic compounds of versatile 11 physical and chemical properties using well known all-carbon systems as scaffolds. Among the various BN 12 13 doped PAHs synthesized so far one could distinguish two categories. The most common one, comprises 14 systems in which BN units replace aromatic CC bonds. The second one, in which this study aims to, refers 15 16 to systems wherein the BN unit replaces intercyclic CC bonds linking two independent aromatic sextets 17 18 within the framework of a given PAH. In this work, starting from a reference molecule belonging to the 19 latter category, namely the pyridine-adduct of borazine, we open the subject of polyaromatic hydrocarbons 20 21 doped with intercyclic boron nitrogen bonds. Our results, based on state of the art ab-initio and DFT 22 wavefunction methods, suggests that intercyclic BN bonds, referred in the literature as “N→B dative 23 24 bonds”, if successfully incorporated to (in)finite polyaromatic sections may alter the optical absorption 25 26 profiles of the parental systems in a greater extent than typical BN aromatic units. Specifically, we predict 27 and comprehensively interpret the capacity of N→B dative bonds to switch-on extra-strong one- and two- 28 29 photon quantum transitions followed by intense transfer of charge. The strong excited states alternation 30 triggered by the presence of N→B dative bonds, may unleash exceptionally high non-linear-optical (NLO) 31 32 optical responses and could find a prosper ground in organic optoelectronic technologies. 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 2 59 60 ACS Paragon Plus Environment Page 3 of 44 The Journal of Physical Chemistry 1 2 3 1. Introduction 4 5 6 Polyaromatic hydrocarbons (PAHs) doped with one or more B-N units have attracted tremendous 7 attention1,2,3,4,5,6 in the recent years owed to their potential applications in areas expanding from organic 8 7,8,9 10 9 optoelectronics and energy to molecular biology. The driving scientific hypothesis behind these 10 attempts is that the replacement of a CC bond with a BN unit may alter the electronic structure and 11 12 electrooptic behavior of the parental system without distorting its spatial structure nor changing its total 13 number of electrons. Therefore, starting from a simple PAH one might fabricate an entirely new chemical 14 15 space11 of BN doped isosteres profiting of the available permutations in terms of doping sites and 16 12 17 orientation of the embedded units. A representative example can be found in the work of, Liu et al. 18 demonstrating that six BN isosteres of identical planar shape but different optical absorption profiles could 19 20 be engineered using the molecule of naphthalene as scaffold. Also, very recently Bonifazi and co-workers13 21 succeeded in replacing the carbon atoms at the zigzag periphery of a benzo[fg]tetracenyl derivative with a 22 23 “NBN triads” and they demonstrated their potential in forming strong H-bonded complexes. 24 25 One of the key molecular properties that should be directly affected from BN doping is the molecular 26 dipole moment. This can be easily understood considering the electronegativity difference between boron 27 28 and nitrogen which should create a local separation of charge within a given PAH. Therefore, upon BN 29 doping a nonpolar PAH can be immediately converted to a polar molecule preserving its spatial structure 30 31 and thermodynamic stability. Going a step further, if multi-BN doping14 is applied, one can potentially tune 32 or cancel the polarity of the final product by controlling the occurring additive effects via the relative 33 34 orientation of the embedded BN units. 35 15,16,17 36 Bearing in mind the Taylor expansion in Eq(1) that describes the induced dipole moment (Δμ) of 37 a molecule in the presence of a uniform homogenous static electric field (F), it can be easily deducted that 38 39 BN doping should impact an entire “ecosystem” of molecular properties widely known as the linear (α) 40 dipole polarizabilities and the first and second dipole hyperpolarizabilities (β, γ). 41 42 1 1 F F 2 F 3 .... (1) 43 2 6 44 45 These field dependent molecular properties are of vital scientific and technological importance in the realm 46 47 of photonics since they govern the non-linear optical behavior of molecules and materials.18 48 Based on the above hypothesis and relying on previous experience in nanographene systems,19,20,21 in 49 50 this work we open the subject of the non-linear optical properties of PAHs and nanographenes doped with 51 boron nitrogen dative bonds. A dative bond22,23 denoted in the literature as D→A, is formed between two 52 53 fragments, one playing the role of an electron donor (D) and the other role an acceptor (A). In terms of 54 55 simplified valence bond theory, within a dative bond, the donor atom offers an entire “pair of electrons” to 56 57 58 3 59 60 ACS Paragon Plus Environment The Journal of Physical Chemistry Page 4 of 44 1 2 3 the occurring bonding while the acceptor contributes with a vacant orbital. The major feature that 4 5 distinguishes a dative bond from a covalent one is that, upon rupture, the former should preferably yield 6 two neutral species of vanishing spin polarization or in some cases two spin polarized charged species.22 7 8 Instead, a covalent bond should deliver either two spin-polarized fragments or two oppositely charged 9 10 species. At the atomic level, D→A dative bonds feature stronger polarities and greater lengths than typical 11 covalent bonds, but they are also characterized by lesser stability. Nevertheless, the past decades a series of 12 24,25,16 13 stable polyaromatic molecules have been successfully synthesized and studied proving the viability 14 of dative bonds between boron and nitrogen, especially when an N→B unit participates in polyaromatic 15 16 networks.
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