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Erratum: First-Principles Theory of Correlated Transport through Nanojunctions [Phys. Rev. Lett. 94, 116802 (2005)] (open access)

Erratum: First-Principles Theory of Correlated Transport through Nanojunctions [Phys. Rev. Lett. 94, 116802 (2005)]

This article provides the correction of an equation that was misprinted in Physical Review Letters 94, 116802 (2005).
Date: May 6, 2005
Creator: Ferretti, A.; Calzolari, Arrigo; Di Felice, Rosa; Manghi, Franca; Caldas, Marilia J.; Buongiorno Nardelli, Marco et al.
Object Type: Article
System: The UNT Digital Library
Raman Studies of Molecular Dynamics and Interactions in Liquids (open access)

Raman Studies of Molecular Dynamics and Interactions in Liquids

In order to explore the N-H stretching region of aliphatic amines, we performed a study of the Raman spectrum of n-propylamine at various concentrations in cyclohexane. Statistical analysis provided evidence of a second symmetric stretching vibration, which we were able to assign to nonhydrogen bonded NH2 groups. To obtain additional evidence on the existence of monomers in n-propylamine and to further study hydrogen bonding and Fermi resonance in aliphatic amines, we extended the investigation to the analysis of the Raman spectrum of this compound over an extended range of temperature in the neat liquid phase. This study corroborated our finding that the peak previously assigned to the symmetric stretching mode of hydrogen bonded amines is actually composed of two bands. Furthermore, trends in both the resolved band parameters and the Fermi resonance analysis were tabulated, allowing one to monitor the change in the N-H valence region with concentration and temperature.
Date: May 1984
Creator: Friedman, Barry R. (Barry Richard)
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Molecular Dynamics and Interactions in Liquids (open access)

Molecular Dynamics and Interactions in Liquids

Various modern spectroscopies have been utilized with considerable success in recent years to probe the dynamics of vibrational and reorientational relaxation of molecules in condensed phases. We have studied the temperature dependence of the polarized and depolarized Raman spectra of various modes in the following dihalomethanes: dibromomethane, dichloromethane, dichloromethane-d2, and bromochloromethane. Among other observed trends, we have found the following: Vibrational dephasing times calculated from the bend) and (C-Br stretch) lineshapes are of the same magnitude in CI^B^. The vibrational dephasing time of [C-D(H) stretch] is twice as long in CD2Cl2 as in CH-^C^, and the relaxation time of (C-Cl stretch) is greater in CI^C^ than in CD2CI2. Isotropic relaxation times for all three stretching vibrations are significantly shorter in C^BrCl than in CI^C^ or CI^B^. Application of the Kubo model revealed that derived modulation times are close to equal for equivalent vibrations in the various dihalomethanes. Thus, the more efficient relaxation of the A^ modes in CE^BrCl can be attributed almost entirely to the broader mean squared frequency perturbation of the vibrations in this molecule.
Date: May 1985
Creator: Chen, Jen Hui
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Synthesis of Anthracyclines Related to Adriamycin (open access)

Synthesis of Anthracyclines Related to Adriamycin

This dissertation reports the preparation of several types of anthraquinones structurally related to adriamycin. It describes the synthesis of two types of 2-aminoquinizarin compounds. It also presents two new syntheses of a heterocyclic tetracyclic ring system, similar to the aglicone ring system of adriamycin. A series of 2-aminoquinizarins was prepared by adding several primary amines to quinizarin. Quinizarin was shown to be essentially inert toward secondary amines. Several secondary amine adducts with quinizarin have been prepared, however, by treating the bis-boroacetate ester of quinizarin with the amines. Both types of 2-aminoquinizarin compounds exhibit outstanding potential for possessing antineoplastic activity, and several have been submitted to the National Cancer Institute for testing in their screening program for antineoplastic agents.
Date: May 1981
Creator: White, Roger J.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Chlorosulfonic Acid Reactions with Saturated Hydrocarbons (open access)

Chlorosulfonic Acid Reactions with Saturated Hydrocarbons

This thesis examines the reactions of hydrocarbons exposed to chlorosulfonic acid in order to establish the reaction rate and associated molecular structure of each compound.
Date: May 1939
Creator: Stubblefield, H. L.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Mechanisms of Methane C–H Activation and Oxy-insertion Via Small Transition Metal Complexes: a DFT Computational Investigation (open access)

The Mechanisms of Methane C–H Activation and Oxy-insertion Via Small Transition Metal Complexes: a DFT Computational Investigation

Our country continues to demand clean renewable energy to meet the growing energy needs of our time. Thus, natural gas, which is 87% by volume of methane, has become a hot topic of discussion because it is a clean burning fuel. However, the transportation of methane is not easy because it is a gas at standard temperature and pressure. The usage of transition metals for the conversion of small organic species like methane into a liquid has been a longstanding practice in stoichiometric chemistry. Nonetheless, the current two-step process takes place at a high temperature and pressure for the conversion of methane and steam to methanol via CO + H2 (syngas). The direct oxidation of methane (CH4) into methanol (CH3OH) via homogeneous catalysis is of interest if the system can operate at standard pressure and a temperature less than 250 C. Methane is an inert gas due to the high C-H bond dissociation energy (BDE) of 105 kcal/mol. This dissertation discusses a series of computational investigations of oxy-insertion pathways to understand the essential chemistry behind the functionalization of methane via the use of homogeneous transition metal catalysis. The methane to methanol (MTM) catalytic cycle is made up of two key …
Date: May 2014
Creator: Prince, Bruce M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Targeted and Metal-loaded Polymeric Nanoparticles As Potential Cancer Therapeutics (open access)

Targeted and Metal-loaded Polymeric Nanoparticles As Potential Cancer Therapeutics

Polymeric nanoparticles were designed, synthesized, and loaded with metal ions to explore the therapeutic potential for transition metals other than platinum found in cisplatin. Nanoparticles were synthesized to show the potential for polymer based vectors. Metal loading and release were characterized via Inductively Coupled Plasma Mass Spectrometry (ICP MS), Energy Dispersive X-Ray Spectroscopy (EDX), X-Ray Photoelectron Spectroscopy (XPS), and Elemental Analysis. Targeting was attempted with the expectation of observed increased particle uptake by cancer cells with flow cytometry and fluorescence microscopy. Results demonstrated that a variety of metals could be loaded to the nano-sized carriers in an aqueous environment, and that the release was pH-dependent. Expected increased targeting was inconsistent. The toxicity of these particles was measured in cancer cells where significant toxicity was observed in vitro via dosing of high copper-loaded nanoparticles and slight toxicity was observed in ruthenium-loaded nanoparticles. No significant toxicity was observed in cells dosed with metal-free nanoparticles. Future research will focus on ruthenium loaded polymeric nanoparticles with different targeting ligands dosed to different cell lines for the aim of increased uptake and decreased cancer cell viability.
Date: May 2014
Creator: Harris, Alesha N.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Pseudopotential-Based Correlation Consistent Composite Approach (rp-ccCA) for First- and Second-Row Transition Metal Thermochemistry (open access)

Pseudopotential-Based Correlation Consistent Composite Approach (rp-ccCA) for First- and Second-Row Transition Metal Thermochemistry

This article uses the relativistic-pseudopotential correlation consistent approach (rp-ccCA) to determine the enthalpy of formation of 24 first row (3d) transition metal compounds.
Date: May 22, 2015
Creator: Manivasagam, Sindhu; Laury, Marie L. & Wilson, Angela K.
Object Type: Article
System: The UNT Digital Library
Ligand-field effects for the 3p photoelectron spectra of Cr2O3 (open access)

Ligand-field effects for the 3p photoelectron spectra of Cr2O3

This article discusses ligand-field effects for the 3p photoelectron spectra of Cr2O3.
Date: May 28, 2004
Creator: Bagus, Paul S.; Ilton, Eugene S. & Rustad, James R.
Object Type: Article
System: The UNT Digital Library
Many-body effects in the 4f x-ray photoelectron spectroscopy of the U5+ and U4+ free ions (open access)

Many-body effects in the 4f x-ray photoelectron spectroscopy of the U5+ and U4+ free ions

This article discusses many-body effects in the 4f x-ray photoelectron spectroscopy of the U5+ and U4+ free ions.
Date: May 31, 2005
Creator: Ilton, Eugene S. & Bagus, Paul S.
Object Type: Article
System: The UNT Digital Library
Investigation of the Gas-Phase Kinetics of the Reaction K + SO₂ + Ar (open access)

Investigation of the Gas-Phase Kinetics of the Reaction K + SO₂ + Ar

Article on an investigation of the gas-phase kinetics of the reaction K + SO₂ + Ar.
Date: May 1993
Creator: Goumri, Abdellatif; Laakso, Dianna; Rocha, John-David Ray; Francis, Elizabeth & Marshall, Paul
Object Type: Article
System: The UNT Digital Library
IUPAC-NIST Solubility Data Series. 99. Solubility of Benzoic Acid and Substituted Benzoic Acids in Both Neat Organic Solvents and Organic Solvent Mixtures. (open access)

IUPAC-NIST Solubility Data Series. 99. Solubility of Benzoic Acid and Substituted Benzoic Acids in Both Neat Organic Solvents and Organic Solvent Mixtures.

Article on the solubility of benzoic acid and substituted benzoic acids in both neat organic solvents and organic solvent mixtures.
Date: May 15, 2013
Creator: Acree, William E. (William Eugene)
Object Type: Article
System: The UNT Digital Library
Limiting Diffusion Coefficients for Ions and Nonelectrolytes in Solvents Water, Methanol, Ethanol, Propan-1-ol, Butan-1-ol, Octan-1-ol, Propanone and Acetonitrile at 298 K, Analyzed Using Abraham Descriptors (open access)

Limiting Diffusion Coefficients for Ions and Nonelectrolytes in Solvents Water, Methanol, Ethanol, Propan-1-ol, Butan-1-ol, Octan-1-ol, Propanone and Acetonitrile at 298 K, Analyzed Using Abraham Descriptors

Article describes study demonstrating that solute hydrogen bond acidity, solute hydrogen bond basicity and solute volume all lower the diffusion constants of ions and nonelectrolytes in the various solvents studied.
Date: May 21, 2019
Creator: Abraham, M. H. (Michael H.) & Acree, William E. (William Eugene)
Object Type: Article
System: The UNT Digital Library
Correlation of the Solubilizing Abilities of 1-Butyl-1-methyl-pyrrolidinium Tris(pentafluoroethyl)-trifluorophosphate, 1-Butyl-1-methylpyrrolidinium Triflate and 1-Methoxyethyl-1-methylmorpholinium Tris(pentafluoroethyl) trifluorophosphate (open access)

Correlation of the Solubilizing Abilities of 1-Butyl-1-methyl-pyrrolidinium Tris(pentafluoroethyl)-trifluorophosphate, 1-Butyl-1-methylpyrrolidinium Triflate and 1-Methoxyethyl-1-methylmorpholinium Tris(pentafluoroethyl) trifluorophosphate

This article discusses the correlation of the solubilizing abilities.
Date: May 2013
Creator: Twu, Pamela; Anderson, Jared L.; Stephens, Timothy W.; Wilson, Anastasia; Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
Object Type: Article
System: The UNT Digital Library
Thermochemical Excess Properties of Multicomponent Systems: Representation and Estimation from Binary Mixing Data (open access)

Thermochemical Excess Properties of Multicomponent Systems: Representation and Estimation from Binary Mixing Data

Article on the thermochemical excess properties of multicomponent systems and representation and estimation from binary mixing data.
Date: May 1, 1983
Creator: Bertrand, Gary L.; Acree, William E. (William Eugene) & Burchfield, Thomas E.
Object Type: Article
System: The UNT Digital Library
The Dissociation Enthalpies of Terminal (N--O) Bonds in Organic Compounds (open access)

The Dissociation Enthalpies of Terminal (N--O) Bonds in Organic Compounds

Article on the dissociation enthalpies of terminal (N-O) bonds in organic compounds.
Date: May 27, 2005
Creator: Acree, William E. (William Eugene); Pilcher, Geoffrey & Silva, Maria D. M. C. Ribeiro da
Object Type: Article
System: The UNT Digital Library
Selectivity and Mechanism of Hydrogen Atom Transfer by an Isolable Imidoiron (III) Complex (open access)

Selectivity and Mechanism of Hydrogen Atom Transfer by an Isolable Imidoiron (III) Complex

This article discusses a mechanistic study of hydrogen atom transfer by an isolable iron (III) imido complex, LᴹᵉFeNAd (Lᴹᵉ = bulky β-diketiminate ligand, 2,4-bis(2,6-diisopropylphenylimido)pentyl; Ad = 1-adamantyl).
Date: May 12, 2011
Creator: Cowley, Ryan E.; Eckert, Nathan A.; Vaddadi, Sridhar; Figg, Travis M.; Cundari, Thomas R., 1964- & Holland, Patrick L.
Object Type: Article
System: The UNT Digital Library
C-H Functionalization Reactivity of a Nickel-Imide (open access)

C-H Functionalization Reactivity of a Nickel-Imide

This article discusses C-H functionalization reactivity of a Nickel-Imide.
Date: May 22, 2012
Creator: Wiese, Stefan; McAfee, Jason L.; Pahls, Dale R.; McMullin, Claire L.; Cundari, Thomas R., 1964- & Warren, Timothy H.
Object Type: Article
System: The UNT Digital Library
Hydrogen-Deuerium Exchange between TpRu(PMe3)(L)X (L = PMe3 and X = OH, OPh, Me, Ph, or NHPh; L = NCMe and X = Ph) and Deuterated Arene Solvents: Evidence for Metal-Mediated Processes (open access)

Hydrogen-Deuerium Exchange between TpRu(PMe3)(L)X (L = PMe3 and X = OH, OPh, Me, Ph, or NHPh; L = NCMe and X = Ph) and Deuterated Arene Solvents: Evidence for Metal-Mediated Processes

This article discusses evidence for metal-mediated processes.
Date: May 24, 2006
Creator: Feng, Yuee; Lail, Marty; Foley, Nicholas A.; Gunnoe, T. Brent; Barakat, Khaldoon A.; Cundari, Thomas R., 1964- et al.
Object Type: Article
System: The UNT Digital Library
Comparative Reactivity of TpRu(L)(NCMe)Ph (L = CO or PMe3): Impact of Ancillary Ligand L on Activation of Carbon-Hydrogen Bonds Including Catalytic Hydroarylation and Hydrovinylation/Oligomerization of Ethylene (open access)

Comparative Reactivity of TpRu(L)(NCMe)Ph (L = CO or PMe3): Impact of Ancillary Ligand L on Activation of Carbon-Hydrogen Bonds Including Catalytic Hydroarylation and Hydrovinylation/Oligomerization of Ethylene

Article discussing research on the comparative reactivity of TpRu(L)(NCMe)Ph (L = CO or PMe3) and the impact of ancillary ligand L on activation of carbon-hydrogen bonds including catalytic hydroarylation and hyrdovinylation/oligomerization of ethylene.
Date: May 9, 2007
Creator: Foley, Nicholas A.; Lail, Marty; Lee, John P.; Gunnoe, T. Brent; Cundari, Thomas R., 1964- & Petersen, Jeffrey L.
Object Type: Article
System: The UNT Digital Library
3-Center-4-Electron Bonding in [(silox)2Mo=NtBu]2(μ-Hg) Controls Reactivity while Frontier Orbitals Permit a Dimolybdenum π-Bond Energy Estimate (open access)

3-Center-4-Electron Bonding in [(silox)2Mo=NtBu]2(μ-Hg) Controls Reactivity while Frontier Orbitals Permit a Dimolybdenum π-Bond Energy Estimate

Article describing research on 3-center-4-electron bonding in [(silox)2Mo=NtBu]2(mu-Hg).
Date: May 18, 2005
Creator: Rosenfeld, Devon C.; Wolczanski, Peter T.; Barakat, Khaldoon A.; Buda, Corneliu & Cundari, Thomas R., 1964-
Object Type: Article
System: The UNT Digital Library
An Effective Core Potential Study of Transition-Metal Chalcogenides. 1. Molecular Structure (open access)

An Effective Core Potential Study of Transition-Metal Chalcogenides. 1. Molecular Structure

This article discusses an effective core potential study of transition-metal chalcogenides O, S, Se, and Te.
Date: May 1994
Creator: Benson, Michael T.; Cundari, Thomas R., 1964-; Lim, Soon J.; Nguyen, Hoang D. & Pierce-Beaver, Karen
Object Type: Article
System: The UNT Digital Library
Small Molecule Elimination from Group IVB (Ti, Zr, Hf) Amido Complexes (open access)

Small Molecule Elimination from Group IVB (Ti, Zr, Hf) Amido Complexes

This article discusses small molecule elimination from group IVB (Ti, Zr, Hf) amido complexes. An ab initio quantum chemical analysis of HX (X = H, CH₃, Cl, NH₂, SiH₃) elimination by group IVB (Ti, Zr, Hf) amidos (H₂(X)M - NH₂ → H₂M = NH + HX), of interest in the context of CVD precursor design, is reported.
Date: May 1993
Creator: Cundari, Thomas R., 1964- & Gordon, Mark S.
Object Type: Article
System: The UNT Digital Library
Calculation of the Surface Tension of Ordinary Organic and Ionic Liquids by Means of a Generally Applicable Computer Algorithm Based on the Group-Additivity Method (open access)

Calculation of the Surface Tension of Ordinary Organic and Ionic Liquids by Means of a Generally Applicable Computer Algorithm Based on the Group-Additivity Method

This article presents the calculation of the surface tension of ordinary organic and ionic liquids, based on a computer algorithm applying a refined group-additivity method.
Date: April 16, 2018
Creator: Naef, Rudolf
Object Type: Article
System: The UNT Digital Library