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Facile and Regioselective C H Bond Activation of Aromatic Substrates by an Fe (II) Complex Involving a Spin-Forbidden Pathway

Description: Article discussing facile and regioselective C H bond activation of aromatic substrates by an Fe(II) complex involving a spin-forbidden pathway.
Date: February 27, 2013
Creator: Kalman, Steven E.; Petit, Alban; Gunnoe, T. Brent; Ess, Daniel H.; Cundari, Thomas R., 1964- & Sabat, Michal
Partner: UNT College of Arts and Sciences

Mn Interstitial Diffusion in (Ga, Mn)As

Description: This article describes a combined theoretical and experimental study of the ferromagnetic semiconductor (Ga, Mn)As which explains the remarkably lard changes observed on low-temperature annealing.
Date: January 23, 2004
Creator: Edmonds, Kevin; Boguslawski, Piotr; Wang, K. Y.; Campion, Richard Paul; Novikov, Sergei; Farley, N. R. S. et al.
Partner: UNT College of Arts and Sciences

Molybdenum and Tungsten Structural Differences are Dependent on ndz2/(n + 1)ѕ Mixing: Comparisons of (silox)3MX/R (M = Mo, W; silox = tBu3SiO)

Description: Article discussing molybdenum and tungsten structural differences being dependent on ndz2/(n + 1)s mixing and a comparison of (silox)3MX/R (M = Mo, W; silox - tBu3SiO).
Date: July 15, 2008
Creator: Kuiper, David S.; Douthwalte, Richard E.; Mayoi, Ana-Rita; Wolczanski, Peter T.; Lobkovsky, Emil B.; Cundari, Thomas R., 1964- et al.
Partner: UNT College of Arts and Sciences

Performance of Density Functional Theory for 3d Transition Metal-Containing Complexes: Utilization of the Correlation Consistent Basis Sets

Description: Article discussing the performance of density functional theory for 3d transition metal-containing complexes and the utilization of the correlation consistent basis sets.
Date: July 2, 2009
Creator: Tekarli, Sammer M.; Drummond, Michael L.; Williams, T. Gavin; Cundari, Thomas R., 1964- & Wilson, Angela K.
Partner: UNT College of Arts and Sciences

Quantitative Computational Thermochemistry of Transition Metal Species

Description: This article discusses quantitative computational thermochemistry of transition metal species. The correlation consistent Composite Approach (ccCA), which has been shown to achieve chemical accuracy (±1 kcal mol⁻¹) for a large benchmark set of main group and s-block metal compounds, is used to compute enthalpies of formation for a set of 17 3d transition metal species.
Date: May 15, 2007
Creator: DeYonker, Nathan J.; Peterson, Kirk A.; Steyl, Gideon; Wilson, Angela K. & Cundari, Thomas R., 1964-
Partner: UNT College of Arts and Sciences

Synthesis and Reactivity of a Coordinatively Unsaturated Ruthenium(II) Parent Amido Complex: Studies of X-H Activation (X = H or C)

Description: Article discussing the synthesis and reactivity of a coordinatively unsaturated Ruthenium(II) parent amido complex and studies of X-H activation (X = H or C).
Date: April 27, 2004
Creator: Conner, David; Jayaprakash, K. N.; Cundari, Thomas R., 1964- & Gunnoe, T. Brent
Partner: UNT College of Arts and Sciences

Modeling Transition Metal Chemistry for Catalytic Functionalization of Molecules

Description: The diversity of transition metal complexes allows for a wide range of chemical processes to be mediated by the metal, from catalysis to surface chemistry. Investigations into the structure and electronic configuration of transition metal complexes allow for tuning of desired species by modifications to the ligands and/or metals to achieve more efficient thermodynamics and kinetics for the process of interest. Transition metals, often used in catalysts for a number of important processes, require detailed descriptions of intermediates, transition states and products to fully characterize a reaction mechanism(s) in order to design more active and efficient catalysts. Computational investigations into inorganic catalysts are explored with the aim of understanding the activity of each species and how modifications of supporting ligands, co-ligands and metals vary the interaction along the reaction pathway. Reported results give important insight into the development of the most active complexes in addition to determining the least active complexes to aid experimental development. This report first investigates the mechanisms of two unique transfer reactions: 1) formation of low coordinate nickel-nitrene ((P~P)Ni=NR; P~P = 1,2-bis(dihydrophosphino)-ethane or 1,2-bis(difluoromethylphosphino)-ethane) complexes as catalysts for nitrogen atom transfer and 2) oxidation of a triphosphorus niobium complex, [(η2-P3SnPh3)Nb(OMe)3], for the transfer of the phosphorus synthon, Ph3SnP3. These reactions have utility in the synthesis of nitrogen and phosphorus containing molecules, respectively, and the results presented provide mechanistic insight into the synthesis of the organometallic intermediates. Additionally, a computational approach towards rational catalyst design was performed on the ruthenium based hydroarylation catalyst TpRu(CO)(Ph) [Tp = hydrido-tris(pyrazolyl)borate]. Targeted modifications at the Tp, metal and co-ligand (CO) sites were studied in order to tune the electronics and sterics of the catalyst. Modifications, through computational methods, provided a more cost- and time-efficient way to study the impact of modifications, which provided direct input into attractive synthetic targets. The research ...
Date: August 2011
Creator: Morello, Glenn
Partner: UNT Libraries

Effects of covalency on the p-shell photoemission of transition metals: MnO

Description: This article discusses the effects of covalency on the p-shell photoemission of transition metals. The treatment of covalency has not been included previously in ab initio theoretical studies of the 2p-shell XPS of transition-metal complexes. In this work, covalent interactions between the metal and ligands are treated on an equal footing with spin-orbit splittings.
Date: April 13, 2006
Creator: Bagus, Paul S. & Ilton, Eugene S.
Partner: UNT College of Arts and Sciences

Reactivity of Five-Coordinate Intermediates Derived from (Chelate) Tetracarbonylmetal (0) Complexes

Description: The reactivity of the [(Phen)Cr(CO)_3] intermediate with phosphines and phosphites (L) has been investigated through ligand-competition studies. This intermediate possesses virtually no ability to discriminate among L. The agreement between reactivity data for the thermal and photochemically-generated intermediates indicates that the same intermediate is produced via each process. Pulsed laser flash photolysis of (n^2-NP)M(CO)_4 (I) (M = Cr, Mo; NP = 1-diethylamino-2-diphenylphosphinoethane) in the absence and presence of P (OPr-i)_3 (L) in 1,2-dichloroethane and chlorobenzene induces unimolecular ring-opening to afford [(n^1-NP)M(CO)_4] (II), in which the bidentate ligand is coordinated through P. Reaction of this intermediate takes place through competitive ring-reclosure and attack at (II) by L to afford (I) and cis-(n^1-NP) (L)M(CO)_4.
Date: December 1983
Creator: Mansour, Saber E. (Saber El-Sayed)
Partner: UNT Libraries