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T.: Leapfrog transformations and polyhedra of Clar type
 J. Chem. Soc., Faraday Trans
, 1994
"... The socalled leapfrog transformation that was first introduced for fullerenes (trivalent polyhedra with 12 pentagonal faces and all other faces hexagonal) is generalised to general polyhedra and maps on surfaces. All spherical polyhedra can be classified according to the i r leapfrog order. A pol ..."
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The socalled leapfrog transformation that was first introduced for fullerenes (trivalent polyhedra with 12 pentagonal faces and all other faces hexagonal) is generalised to general polyhedra and maps on surfaces. All spherical polyhedra can be classified according to the i r leapfrog order. A polyhedron is said to be of Clar type if there exists a set of faces that cover each vertex exactly once. It is shown tha t a fullerene is of Clar type if and only if it is a leapfrog transform of another fu l le rene. Several basic transformations on maps are defined by means of which t h e leapfrog and other transformations can be accomplished. 1.
CHEMICAL GRAPH THEORY OF FIBONACENES
"... Fibonacenes (zigzag unbranched catacondensed benzenoid hydrocarbons) are a class of polycyclic conjugated systems whose molecular graphs possess remarkable properties, often related with the Fibonacci numbers. This article is a review of the chemical graph theory of fibonacenes, with emphasis on th ..."
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Cited by 6 (0 self)
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Fibonacenes (zigzag unbranched catacondensed benzenoid hydrocarbons) are a class of polycyclic conjugated systems whose molecular graphs possess remarkable properties, often related with the Fibonacci numbers. This article is a review of the chemical graph theory of fibonacenes, with emphasis on their Kekulé–structure–related and Clar–structure–related properties.
Normal components, Kekulé patterns, and Clar patterns in plane bipartite graphs
"... As a general case of molecular graphs of polycyclic alternant hydrocarbons, we consider a plane bipartite graph G with a KekulÃ© pattern (perfect matching). An edge of G is called nonfixed if it belongs to some, but not all, perfect matchings of G. Several criteria in terms of resonant cells for de ..."
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Cited by 5 (2 self)
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As a general case of molecular graphs of polycyclic alternant hydrocarbons, we consider a plane bipartite graph G with a KekulÃ© pattern (perfect matching). An edge of G is called nonfixed if it belongs to some, but not all, perfect matchings of G. Several criteria in terms of resonant cells for determining whether G is elementary (i.e. without fixed edges) are reviewed. By applying perfect matching theory developed in plane bipartite graphs, in a unified and simpler way we study the decomposition of plane bipartite graphs with fixed edges into normal components, which is shown useful for resonance theory, in particular, cell and sextet polynomials. Further correspondence between the KekuÃ© patterns and Clar (resonant) patterns are revealed.
Situ Chemical Oxidation of Creosote/Coal Tar Residuals: Experimental and Numerical Investigation
, 2004
"... I herby declare that I am the sole author of this thesis. This is a true copy of the thesis, including any required final version, as accepted by my examiners. I understand that my thesis may be made electronically available to the public ..."
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Cited by 5 (0 self)
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I herby declare that I am the sole author of this thesis. This is a true copy of the thesis, including any required final version, as accepted by my examiners. I understand that my thesis may be made electronically available to the public
kresonance in toroidal polyhexes
"... This paper considers the kresonance of a toroidal polyhex (or toroidal graphitoid) with a string (p, q, t) of three integers (p ≥ 2, q ≥ 2, 0 ≤ t ≤ p − 1). A toroidal polyhex G is said to be kresonant if, for 1 ≤ i ≤ k, any i disjoint hexagons are mutually resonant, that is, G has a Kekulé structu ..."
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Cited by 4 (2 self)
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This paper considers the kresonance of a toroidal polyhex (or toroidal graphitoid) with a string (p, q, t) of three integers (p ≥ 2, q ≥ 2, 0 ≤ t ≤ p − 1). A toroidal polyhex G is said to be kresonant if, for 1 ≤ i ≤ k, any i disjoint hexagons are mutually resonant, that is, G has a Kekulé structure (perfect matching) M such that these hexagons are Malternating (in and off M). Characterizations for 1, 2 and 3resonant toroidal polyhexes are given respectively in this paper.
Clar Sextet Analysis of Triangular, Rectangular and Honeycomb Graphene Antidot Lattices
"... Pristine graphene is a semimetal and thus does not have a band gap. By making a nanometer scale periodic array of holes in the graphene sheet a band gap may form; the size of the gap is controllable by adjusting the parameters of the lattice. The hole diameter, hole geometry, lattice geometry and ..."
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Pristine graphene is a semimetal and thus does not have a band gap. By making a nanometer scale periodic array of holes in the graphene sheet a band gap may form; the size of the gap is controllable by adjusting the parameters of the lattice. The hole diameter, hole geometry, lattice geometry and the separation of the holes are parameters that all play an important role in determining the size of the band gap, which, for technological applications, should be at least of the order of tenths of an eV. We investigate four different hole configurations: the rectangular, the triangular, the rotated triangular and the honeycomb lattice. It is found that the lattice geometry plays a crucial role for size of the band gap: the triangular arrangement displays always a sizable gap, while for the other types only particular hole separations lead to a large gap. This observation is explained using Clar sextet theory, and we find that a sufficient ∗To whom correspondence should be addressed
A Reaction pathway for Nanoparticle Formation
 in Rich Premixed Flames”, Combust. Flame
, 2001
"... Aromatics growth beyond 2, 3ring PAH is analyzed through a radicalmolecule reaction mechanism which, in combination with a previously developed PAH model, is able to predict the size distribution of aromatic structures formed in rich premixed flames of ethylene at atmospheric pressure with C/O ra ..."
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Aromatics growth beyond 2, 3ring PAH is analyzed through a radicalmolecule reaction mechanism which, in combination with a previously developed PAH model, is able to predict the size distribution of aromatic structures formed in rich premixed flames of ethylene at atmospheric pressure with C/O ratios across the soot threshold limit. Modeling results are in good agreement with experimental data and are used to interpret the ultraviolet absorption and the light scattering measured in flames before soot inception. The model shows that the total number concentration of high molecular mass aromatics and the different moments of the size distribution are functions of both the PAH and Hatom concentrations, two quantities which have different trends as functions of the residence time and the C/O ratio. Regimes of nearly stoichiometric or slightly rich premixed combustion are dominated by reactions between aromatics which lead to the formation of particles with sizes of the order of 3 to 4 nm. At higher C/O ratios the formation of nanoparticles is less efficient. Particles with sizes of the order of 2 nm are predicted in flames at the threshold of soot formation, whereas particles with sizes around 1 to 1.5 nm are predicted in fully sooting conditions. © 2001 by The Combustion Institute
Quantum Mechanical Study of Molecular Weight Growth Process by Combination of Aromatic Molecules
"... Formation pathways for highmolecularmass compound growth are presented, showing why reactions between aromatic moieties are needed to explain recent experimental findings. These reactions are then analyzed by using quantum mechanical density functional methods. A sequence of chemical reactions bet ..."
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Formation pathways for highmolecularmass compound growth are presented, showing why reactions between aromatic moieties are needed to explain recent experimental findings. These reactions are then analyzed by using quantum mechanical density functional methods. A sequence of chemical reactions between aromatic compounds (e.g., phenyl) and compounds containing conjugated double bonds (e.g., acenaphthylene) was studied in detail. The sequence begins with the Habstraction from acenaphthylene to produce the corresponding radical, which then furnishes higher aromatics through either a twostep radical–molecule reaction or a direct radical–radical addition to another aromatic radical. Iteration of this mechanism followed by rearrangement of the carbon framework ultimately leads to highmolecularmass compounds. This sequence can be repeated for the formation of highmolecularmass compounds. The distinguishing features of the proposed model lie in the chemical specificity of the routes considered. The aromatic radical attacks the double bond of fivememberedring polycyclic aromatic hydrocarbons. This involves specific compounds that are exceptional soot precursors as they form resonantly stabilized radical intermediates, relieving part of the large strain in the fivemembered rings by formation of linear aggregates. © 2001 by The Combustion Institute