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Electronic Structure, Chemical Bonding, and Electronic Delocalization of Organic and Inorganic Systems with Three-Dimensional Or Excited State Aromaticity

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ELECTRONIC STRUCTURE, CHEMICAL BONDING, AND ELECTRONIC DELOCALIZATION OF ORGANIC AND INORGANIC SYSTEMS WITH THREE-DIMENSIONAL OR EXCITED STATE AROMATICITY Ouissam El Bakouri El Farri Per citar o enllaçar aquest document: Para citar o enlazar este documento: Use this url to cite or link to this publication: http://hdl.handle.net/10803/565444 ADVERTIMENT. L'accés als continguts d'aquesta tesi doctoral i la seva utilització ha de respectar els drets de la persona autora. Pot ser utilitzada per a consulta o estudi personal, així com en activitats o materials d'investigació i docència en els termes establerts a l'art. 32 del Text Refós de la Llei de Propietat Intel·lectual (RDL 1/1996). Per altres utilitzacions es requereix l'autorització prèvia i expressa de la persona autora. En qualsevol cas, en la utilització dels seus continguts caldrà indicar de forma clara el nom i cognoms de la persona autora i el títol de la tesi doctoral. No s'autoritza la seva reproducció o altres formes d'explotació efectuades amb finalitats de lucre ni la seva comunicació pública des d'un lloc aliè al servei TDX. Tampoc s'autoritza la presentació del seu contingut en una finestra o marc aliè a TDX (framing). Aquesta reserva de drets afecta tant als continguts de la tesi com als seus resums i índexs. ADVERTENCIA. El acceso a los contenidos de esta tesis doctoral y su utilización debe respetar los derechos de la persona autora. Puede ser utilizada para consulta o estudio personal, así como en actividades o materiales de investigación y docencia en los términos establecidos en el art. 32 del Texto Refundido de la Ley de Propiedad Intelectual (RDL 1/1996). Para otros usos se requiere la autorización previa y expresa de la persona autora. En cualquier caso, en la utilización de sus contenidos se deberá indicar de forma clara el nombre y apellidos de la persona autora y el título de la tesis doctoral. No se autoriza su reproducción u otras formas de explotación efectuadas con fines lucrativos ni su comunicación pública desde un sitio ajeno al servicio TDR. Tampoco se autoriza la presentación de su contenido en una ventana o marco ajeno a TDR (framing). Esta reserva de derechos afecta tanto al contenido de la tesis como a sus resúmenes e índices. WARNING. Access to the contents of this doctoral thesis and its use must respect the rights of the author. It can be used for reference or private study, as well as research and learning activities or materials in the terms established by the 32nd article of the Spanish Consolidated Copyright Act (RDL 1/1996). Express and previous authorization of the author is required for any other uses. In any case, when using its content, full name of the author and title of the thesis must be clearly indicated. Reproduction or other forms of for profit use or public communication from outside TDX service is not allowed. Presentation of its content in a window or frame external to TDX (framing) is not authorized either. These rights affect both the content of the thesis and its abstracts and indexes. DOCTORAL THESIS: Electronic structure, chemical bonding, and electronic delocalization of organic and inorganic systems with three- dimensional or excited state aromaticity Ouissam El Bakouri El Farri 2017 Doctoral programme in Chemistry Supervised by: Dr. Miquel Solà i Puig, Dr. Jordi Poater Teixidor and Dr. Ferran Feixas Geronès Tutor: Dr. Miquel Solà i Puig Presented in partial fulfillment of the requirements for a doctoral degree from the University of Girona Prof. Dr. Miquel Solà i Puig, and Dr. Ferran Feixas Geronès from University of Girona; and Dr. Jordi Poater Teixidor from University of Barcelona, WE DECLARE: That the thesis entitled Electronic structure, chemical bonding, and electronic delocalization of organic and inorganic systems with three-dimensional or excited state aromaticity, presented by Ouissam El Bakouri El Farri to obtain the doctoral degree, has been completed under our supervision and meets the requirements to opt for an International Doctorate. For all the intents and purposes, we hereby sign this document. Prof. Dr. Miquel Solà i Puig Dr. Jordi Poater Teixidor Dr. Ferran Feixas Geronès Girona, September 25th, 2017 Dedicated to my family “However difficult life may seem, there is always something you can do and succeed at.” Stephen Hawking Full list of publications List of publications resulting from this thesis 2S+1 1) El Bakouri, O.; Duran, M.; Poater, J.; Feixas, F.; Solà, M. Octahedral aromaticity in A1g q X6 clusters (X = Li–C and Be–Si, S = 0–3, and q = −2 to +4). Phys. Chem. Chem. Phys. 2016, 18, 11700. 2− 2− 2− 2) El Bakouri, O.; Solà, M.; Poater, J. Planar vs. three-dimensional X6 , X2Y4 , and X3Y3 (X, Y = B, Al, Ga) metal clusters: an analysis of their relative energies through the turn- upside-down approach. Phys. Chem. Chem. Phys. 2016, 18, 21102. 3) El Bakouri, O.; Poater, J.; Feixas, F.; Solà, M. Exploring the validity of the Glidewell– Lloyd extension of Clar’s π-sextet rule: assessment from polycyclic conjugated hydrocarbons. Theor. Chem. Acc. 2016, 135, 205. 4) Jorner, K.; Dreos, A.; Emanuelsson, R.; El Bakouri, O.; Fdez. Galván, I.; Börjesson, K.; Feixas, F.; Lindh, R.; Zietz, B.; Moth-Poulsen, K.; Ottosson, H. Unraveling factors leading to efficient norbornadiene–quadricyclane molecular solar-thermal energy storage systems. Mater. Chem. A 2017, 5, 12369. 5) Ayub, R.; El Bakouri, O.; Jorner, K.; Solà, M.; Ottosson, H. Can Baird’s and Clar’s Rules Combined Explain Triplet State Energies of Polycyclic Conjugated Hydrocarbons with Fused 4nπ- and (4n + 2)π-Rings? J. Org. Chem. 2017, 82, 6327. 6) El Bakouri, O.; Postils, V.; Garcia-Borràs, M.; Duran, M.; Luis, J. M.; Matito, E.; Calvello, S.; Soncini, A.; Feixas, F.; Solà, M. Metallaelectrides: A molecular model for the metallic bonding. To be submitted. 7) El Bakouri, O.; Postils, V.; Feixas, F.; Solà, M.; Matito, E. Electride, metal, and metallaelectride behavior in lithium metal clusters. To be submitted. 8) El Bakouri, O.; Garcia-Borràs, M.; M. Girón, R.; Filippone, S.; Martín, N.; Solà, M. On the regioselectivity of the Diels-Alder cycloaddition to C60 in high spin states. To be submitted. My contribution to the publications discussed: As the first author, I carried out the calculations and the writing of the draft for articles 1, 2, 3, 6, 7 and 8. As a co-author, I performed part of the computational study, discussion and revision of papers 4 and 5. List of publications not included in this thesis 9) El-Hamdi, M.; El Bakouri, O.; Salvador, P.; Abdelouahid, B. A.; El Begrani, M. S.; Poater, J.; Solà, M. Analysis of the Relative Stabilities of Ortho, Meta, and Para MClY(XC4H4)(PH3)2 Heterometallabenzenes (M = Rh, Ir; X = N, P; Y = Cl and M = Ru, Os; X = N, P; Y = CO). Organometallics 2013, 32, 4892. 10) El Bakouri, O.; Fernández, M.; Brun, S.; Pla-Quintana, A.; Roglans, A. A simple catalytic system based on PdCl2(CH3CN)2 in water for cross-coupling reactions using diazonium salts. Tetrahedron 2013, 69, 9761. 11) El Bakouri, O.; Cassú, D.; Solà, M.; Parella, T.; Pla-Quintana, A.; Roglans, A. A new mild synthetic route to N-arylated pyridazinones from aryldiazonium salts. Chem. Commun. 2014, 50, 8073. 12) El Bakouri, O.; Jorner, K.; Solà, M.; Ottosson, H. Triplet states of pentalenes intrafused with benzo- and naphtho-segments: When Baird-aromatic and when Hückel-aromatic? To be submitted. 13) El Bakouri, O.; Feixas, F.; Solà, M. Critical assessment of aromaticity indices. To be submitted. List of acronyms Abbreviation Description ACID Anisotropy of the Induced Current Density AIM Atom In a Molecule AO Atomic Orbital AOM Atomic Overlap Matrix ASE Aromatic Stabilization Energy BCP Bond Critical Point CASSCF Complete Active Space Self-Consistent field CBD Cyclobutadiene CCP Cage Critical Point CCSD Coupled Cluster Singles and Doubles CCSD(T) Coupled Cluster Singles, Doubles and perturbative Triples CI Conical Intersection CMO Canonical Molecular Orbital COT Cyclooctatetraene CP Critical Point Cp Cyclopentadiene CROHF Coupled-perturbed Restricted Open-Shell Hartree-Fock CTOCD Continuous Transformation Of Current Density DA Diels-Alder DI Delocalization Index DFT Density Functional Theory EDA Energy Decomposition Analysis EMF Endohedral Metallofullerenes ESI Electronic Sharing Indices FLU Aromatic Fluctuation Index FC Franck-Condon GIMIC Gauge-Including Magnetically Induced Current HOMA Harmonic Oscillator Model of Aromaticity HOMO Highest Occupied Molecular Orbital IPR Isolated Pentagon Rule ISC Intersystem Crossing ISE Isomerization Stabilization Energy LI Localization Index MCI Multicenter Index MO Molecular Orbital MP2 Second-order Moller-Plesset Perturbation Theory MR Membered-Ring NBO Natural Bond Orbital NBD Norbornadiene NCI Noncovalent Interactions NCP Nuclear Critical Point NICS Nucleus-Independent Chemical Shift NNA Non-Nuclear Attractor PAH Polycyclic Aromatic Hydrocarbon PCH Polycyclic Conjugated Hydrocarbon PDI Para-Delocalization Index PEN Pentalene PES Potential Energy Surface QC Quadricyclane QCISD Quadratic Configuration Interaction with Single and Double Excitations QTAIM Quantum Theory of Atoms in Molecules RCP Ring Critical Point SOMO Singly Occupied Molecular Orbital TDDFT Time-Dependent Density Functional Theory XCD Exchange-Correlation Density List of figures Figure 1. Resonance structures of benzene (left) and geometry of COT (right). ............... 11 Figure 2. Schematic π-MOs of benzene in its S0 state. .................................................... 12 Figure 3. Hückel and Möbius topologies. ...................................................................... 12 2- Figure 4. Most stable Hückel (top) and Möbius (bottom) isomers of C10H10 with their most respective representative π-MOs. Geometries obtained from reference [48]. Isosurface value at 0.02 a.u. .................................................................................................................... 13 Figure 5. Schematic π-MOs of cyclopropenyl cation (left) and anion (right). ................... 14 Figure 6. Resonance and Clar (in red) structures of phenanthrene (A) and anthracene(C) and Clar structure of triphenylene (B). Reproduced/adapted with permission from reference [60].
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    Research Report by Dr. Kirill Yu. Monakhov – Graduate College 850 “Molecular Modeling 2010 Research Report by Dr. Kirill Yu. Monakhov Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany, Fax: +49-6221-546617. Supervisor: Gerald Linti Abstract In the framework of my Ph.D. thesis, the polynuclear bismuth chemistry has been investigated from different perspectives with the main focus on four types of the chemical bonding. Thus, the section of bismuth–bismuth bonding affects redox/metathesis reactions of BiBr3 with bulky lithium silanide Li(thf)3SiPh2tBu in three different ratios, leading to the formation of a Bi–Bi bonded compound, (tBuPh2Si)4Bi2 as one of the reaction products. The · quantum chemical study has been mainly performed to shed light on the processes of oligomerisation of R2Bi radicals and bismuth dimers. That is a major challenge in the context of ''thermochromicity'' and ''closed-shell interactions'' in inorganic chemistry of organobismuth compounds with homonuclear Bi–Bi bonds. The section of bismuth–transition-metal bonding gives a deep insight into the structures, the chemical bonding and the 4– electronic behavior of heteronuclear bulky Bi–Fe cage-like clusters, cubic [Bi4Fe8(CO)28] and seven-vertex [Bi4Fe3(CO)9], on the experimental and theoretical level. The section of bonding in bismuth–cyclopentadienyl compounds represents a detailed theoretical and experimental study of molecular systems based on 2+ cyclopentadienyl bismuth units such as (C5R5)Bi , [(C5R5)Bi]n and (C5R5)BiX2 (R = H, Me; X = F, Cl, Br, I; n = 1−4) in order to develop an effective adjustment of their electronic and bonding behavior and then, to be able to manipulate highly fluxional Bi–C5R5 bonds.
  • All-Metal Aromatic Cationic Palladium Triangles Can Mimic Aromatic Donor Ligands with Lewis Acidic Cite This: Chem

    All-Metal Aromatic Cationic Palladium Triangles Can Mimic Aromatic Donor Ligands with Lewis Acidic Cite This: Chem

    Chemical Science View Article Online EDGE ARTICLE View Journal | View Issue All-metal aromatic cationic palladium triangles can mimic aromatic donor ligands with Lewis acidic Cite this: Chem. Sci.,2017,8,7394 cations† Yanlan Wang,a Anna Monfredini,c Pierre-Alexandre Deyris,a Florent Blanchard,a Etienne Derat,b Giovanni Maestri *ac and Max Malacriaab We present that cationic rings can act as donor ligands thanks to suitably delocalized metal–metal bonds. This could grant parent complexes with the peculiar properties of aromatic rings that are crafted with main group elements. We assembled Pd nuclei into equilateral mono-cationic triangles with unhindered faces. Like their main group element counterparts and despite their positive charge, these noble-metal rings form stable bonding interactions with other cations, such as positively charged silver atoms, to deliver Received 9th August 2017 the corresponding tetranuclear dicationic complexes. Through a mix of modeling and experimental Accepted 28th August 2017 techniques we propose that this bonding mode is an original coordination-like one rather than a 4- DOI: 10.1039/c7sc03475j Creative Commons Attribution 3.0 Unported Licence. centre–2-electron bond, which have already been observed in three dimensional aromatics. The present rsc.li/chemical-science results thus pave the way for the use of suitable metal rings as ligands. Introduction perpendicular to their plane (Qzz, Fig. 1, bottom), while anions form these interactions with those that have a positive one.7 Aromaticity is a fascinating chemical concept. It provides For decades, chemists have only played with a few nuclei to a unifying picture to account for and predict the properties of construct aromatics, mostly H, C, N and O.