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Full-Text Articles in Other Chemistry
Science Classics, Mark Masthay
Science Classics, Mark Masthay
Chemistry Faculty Publications
An essay on the impact of the works in the Imprints and Impressions: Milestones in Human Progress, an exhibition of rare books from the collection of Stuart Rose. Exhibition was held Sept. 29-Nov. 9, 2014, at the University of Dayton.
Stop Rotating! One Substitution Halts The B19- Motor, Francisco Cervantes-Navarro, Gerarso Martínez-Guajardo, Edison Osorio, Diego Moreno, William Tiznado, Rafael Islas, Kelling J. Donald, Gabriel Merino
Stop Rotating! One Substitution Halts The B19- Motor, Francisco Cervantes-Navarro, Gerarso Martínez-Guajardo, Edison Osorio, Diego Moreno, William Tiznado, Rafael Islas, Kelling J. Donald, Gabriel Merino
Chemistry Faculty Publications
The B19- anion and other boron species have been dubbed ‘Wankel motors’ for the almost barrierless rotation of inner and outer concentric rings relative to each other in these compounds. A single substitution in B19- is shown to shut down the well-established fluxionality in the anion. A carbon atom substituted in the structure to give a neutral CB18 species is shown computationally to enforce bond localization.
Theoretical Design Of Stable Small Aluminium-Magnesium Binary Clusters, Edison Osorio, Alejandro Vasquez, Elizabeth Florez, Fanor Mondragon, Kelling J. Donald, William Tiznado
Theoretical Design Of Stable Small Aluminium-Magnesium Binary Clusters, Edison Osorio, Alejandro Vasquez, Elizabeth Florez, Fanor Mondragon, Kelling J. Donald, William Tiznado
Chemistry Faculty Publications
We explore in detail the potential energy surfaces of the AlxMgy (x, y = 1–4) systems as case studies to test the utility and limitations of simple rules based on electron counts and the phenomenological shell model (PSM) for bimetallic clusters. We find that it is feasible to design stable structures that are members of this set of small Al–Mg binary clusters, using simple electron count rules, including the classical 4n + 2 Hückel model, and the most recently proposed PSM. The thermodynamic stability of the title compounds has been evaluated using several different descriptors, including …
Cbe5e− (E = Al, Ga, In, Tl): Planar Pentacoordinate Carbon In Heptaatomic Clusters, Abril C. Castro, Gerarso Martinez-Guajardo, Thomas Johnson, Jesus M. Ugalde, Yan-Bo Wu, Jose M. Mercero, Thomas Heine, Kelling J. Donald, Gabriel Merino
Cbe5e− (E = Al, Ga, In, Tl): Planar Pentacoordinate Carbon In Heptaatomic Clusters, Abril C. Castro, Gerarso Martinez-Guajardo, Thomas Johnson, Jesus M. Ugalde, Yan-Bo Wu, Jose M. Mercero, Thomas Heine, Kelling J. Donald, Gabriel Merino
Chemistry Faculty Publications
A series of clusters with the general formula CBe5E- (E = Al, Ga, In, Tl) are theoretically shown to have a planar pentacoordinate carbon atom. The structures show a simple and rigid topological framework—a planar EBe4 ring surrounding a C center, with one of the ring Be–Be bonds capped in-plane by a fifth Be atom. The system is stabilized by a network of multicenter σ bonds in which the central C atom is the acceptor, and π systems as well by which the C atom donates charge to the Be and E atoms that encircle it.
Plane And Simple: Planar Tetracoordinate Carbon Centers In Small Moleculesw, Chad Crigger, Bernard K. Wittmaack, Marina Tawfik, Gabriel Merino, Kelling J. Donald
Plane And Simple: Planar Tetracoordinate Carbon Centers In Small Moleculesw, Chad Crigger, Bernard K. Wittmaack, Marina Tawfik, Gabriel Merino, Kelling J. Donald
Chemistry Faculty Publications
A class of neutral 18-electron molecules with planar tetracoordinate carbon (ptC) centers is introduced. We show computationally that when n = 3 the neutral singlet molecule C(BeH)n(BH2)4-n and other isoelectronic (18-valence electron) molecules of main group elements collapse from locally tetrahedral arrangements at the C-center to (near) planar tetracoordinate structures. For C(BeH)3BH2 and C(CH3)(BH2)Li2, for example, the tetrahedral type conformation is not even a minimum on the potential energy surface at the B3PW91, MP2(full), or CCSD levels of theory. The Mg analogue C(MgH)3BH2 …
Shorter Still: Compressing C-C Single Bonds, Gerarso Martinez-Guajardo, Kelling J. Donald, Bernard K. Wittmaack, Miguel Angel Vazquez, Gabriel Merino
Shorter Still: Compressing C-C Single Bonds, Gerarso Martinez-Guajardo, Kelling J. Donald, Bernard K. Wittmaack, Miguel Angel Vazquez, Gabriel Merino
Chemistry Faculty Publications
How short can a C-C single bond get? The bonding in a set of molecules that are related structurally to previously synthesized or theoretically examined systems with short C-C bonds is investigated. According to calculations, a single C-C bond could be compressed to 1.313 A! To the best of our knowledge, this is the shortest single C-C bond reported to date. This shortening is a consequence of a change in the C-C-C bond angle, θ, to minimize strain in the cages and an effort to offset the tension in the surrounding bridges.
Efficient And General Synthesis Of Novel Β-Polyfluoroalkoxy Vinamidinium Salts, Koichiro Kase, Mitsuyoshi Katayama, Takashi Ishihara, Hiroki Yamanaka, John T. Gupton
Efficient And General Synthesis Of Novel Β-Polyfluoroalkoxy Vinamidinium Salts, Koichiro Kase, Mitsuyoshi Katayama, Takashi Ishihara, Hiroki Yamanaka, John T. Gupton
Chemistry Faculty Publications
Novel β-polyfluoroalkoxy vinamidinium salts 3 and/or 4 were synthesized in good yields by the reaction of N-(2- polyfluoroalkoxy-3 ,3-difluoro-1-propenyI)trimethylammonium iodides (2), prepared from N-(2,3,3-trifluoro-1-propenyl)trimethylammonium iodide (1), with secondary amines in MeCN at 70 °C for 1 h. The salts were also obtainable in comparable yields by the one-pot reaction of 1 with sodium polyfluoroalkoxide followed by treatment with amines.