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CreatorTitleDescriptionSubjectDate
251 Blumenthal, Donald K.; Trewhella, JillConformationally dynamic C helix of the RIalpha subunit of protein kinase A mediates isoform-specific domain reorganization upon C subunit binding.Different isoforms of the full-length protein kinase A (PKA) regulatory subunit homodimer (R2) and the catalytic (C) subunit-bound holoenzyme (R2C2) have very different global structures despite similar molecular weights and domain organization within their primary sequences. To date, it has been th...Protein Isoforms; Global Structures; cAMP2005-10-21
252 Morse, Michael DavidResonant two-photon ionization spectroscopy of BNBTriatomic BNB has been produced by laser ablation of a boron nitride rod in a supersonic expansion of helium carrier gas and has been investigated using resonant two-photon ionization spectroscopy in the visible region. The B? 2IIg?X? 2?u + band system has been recorded near 514 nm and is dominated ...2006
253 Miller, Joel StevenMagnetically ordered molecule-based assembliesThe development of molecules and assemblies of molecules exhibiting technologically important bulk properties, such as magnetic ordering, is an important worldwide research focus. Organic- and molecule-based magnets have been discovered and several families have been reported with magnetic orderin...Organic-based; Lattices; Magnets2006
254 Armentrout, Peter B.Thermochemistry of the activation of N2 on iron cluster cations: guided ion beam studies of the reactions of Fen+ (n=1-19) with N2The kinetic energy dependences of the reactions of Fen + (n=1-19) with N2 are studied in a guided ion beam tandem mass spectrometer over the energy range of 0-15 eV. In addition to collision-induced dissociation forming Fem + ions, which dominate the product spectra, a variety of FemN2+ and FemN+ p...Metal clusters; Iron ions; Dinitrogen; Endothermic reactions; Collision-induced dissociation; Bond energies2006
255 Miller, Joel StevenSynthesis of layered (2-D) V-based bimetallic oxalates from non-aqueous media that cannot be synthesized from aqueous mediaThe reaction of (NBu4)3[VIII(ox)3] (1, ox = oxalate) and M(II) (M= Fe, Co, Ni, Cu) ions in MeCN, leads to the isolation of V-based coordination polymers of [N(n-Bu)4][FeIIVIII(ox)3]? 0.30{[N(n-Bu)4](BF4)} (2), [N(n-Bu)4][CoIIVIII(ox)3]?0.75{[N(n-Bu)4](BF4)} (3), [N(n-Bu)4][NiIIVIII(ox)3]?0.20{[N(n...Magnetic; Coupling; Diffraction2006
256 Miller, Joel StevenMagnetic behaviors of the metamagnetic and ferromagnetic phases of [Fe(C5Me5)2][TCNQ] (TCNQ = 7,7,8,8-tetracyano-p-quinodimethane). Determination of the phase diagram for the metamagnetic phaseThe detailed magnetic behaviors of the ferro- (1FO) and metamagnetic (1MM) phases of [FeCp*2][TCNE] (Cp* = pentamethylcyclopentadienide; TCNE = tetracyanoethylene) aligned parallel to the applied magnetic field, H, were obtained using eicosane (E). The Tc for 1FO is 3.1 K from the maximum in the fr...Properties; Temperature; Ordering2006
257 Poulter, Charles DaleLethal mutations in the isoprenoid pathway of salmonella entericaEssential isoprenoid compounds are synthesized using the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway in many gram-negative bacteria, some gram-positive bacteria, some apicomplexan parasites, and plant chloroplasts. The alternative mevalonate pathway is found in archaea and eukaryotes, includin...Isoprenoids; Mutation; Bacteria; Antimicrobials2006
258 Morse, Michael DavidInfrared diode laser spectroscopy of jet-cooled NiCO, Ni(CO)?(??CO), and NI(CO)?(c??O)Gas phase infrared spectroscopic investigations of the CO vibration of jet-cooled NiCO, Ni(CO)3(13CO), and Ni(CO)3(C18O) are reported. The spectra were obtained using a recently assembled pulsed-discharge slit-jet IR diode laser spectrometer. The rotationally resolved spectrum of NiCO was collected ...2006
259 Armentrout, Peter B.Activation of methane by gold cations: guided ion beam and theoretical studiesThe potential energy surface for activation of methane by the third-row transition metal cation, Au+, is studied experimentally by examining the kinetic energy dependence of this reaction using guided ion beam tandem mass spectrometry. A flow tube ion source produces Au+ primarily in its 1S0 (5d10) ...2006
260 Morse, Michael DavidSpin-forbidden c??+??X??+ band system of YFOptical spectra of jet-cooled diatomic YF have been recorded using resonant two-photon ionization spectroscopy. A vibrational progression corresponding to the c 3?1+?X 1?+ system has been identified. The vibrational frequency ?e' and anharmonicity ?'exe' of the c 3?+ state are 546.70 and 2.45 cm?1,...2007
261 Morse, Michael DavidRotationally resolved spectra of jet-cooled RuSiWe report the first gas-phase spectroscopic investigation of diatomic ruthenium silicide (RuSi). The molecules were produced by laser ablation of a Ru disk into a flow of helium carrier gas containing 0.5% SiH4, and were cooled in a supersonic expansion. The RuSi molecules were then studied using re...2007
262 Morse, Michael DavidRotationally resolved spectroscopy of jet-cooled NbMoRotationally resolved resonant two-photon ionization spectra of jet-cooled NbMo are reported for the first time. A vibronic spectrum of NbMo was recorded in the 17 300?22 300 cm?1 spectral region. Although the observed bands could not be grouped into electronic band systems, four excited vibronic le...2007
263 Morse, Michael DavidRotationally resolved spectra of jet-cooled VMoThe Author's report the first gas-phase spectroscopic investigation of diatomic vanadium molybdenum (VMo). The molecules were produced by laser ablation of a VMo alloy disk and cooled in a helium supersonic expansion. The jet-cooled VMo molecules were studied using resonant two-photon ionization sp...2007
264 Armentrout, Peter B.Statistical modeling of sequential collision-induced dissociation thresholdsThermochemistry determined from careful analysis of the energy dependence of cross sections for collision-induced dissociation (CID) reactions has primarily come from the primary dissociation channel. Higher order dissociations generally have thresholds measured to be higher than the thermodynamic ...Collision-induced dissociation; Endothermic reactions2007
265 Miller, Joel StevenFormation of Ni[C4(CN)8] from the reaction of Ni(COD)2 (COD = 1,5-cyclooctadiene) with TCNE in THFThe dissolution of Ni(COD)2 (COD = 1,5-cyclooctadiene) into dichloromethane leads to decomposition and formation of a room temperature magnetic material, whereas the reaction of Ni(COD)2 and tetracyanoethylene (TCNE) in THF forms paramagnetic materials including NiII[C4(CN)8](THF)2.xTHF. These resu...Dinuclear complexes2007
266 Miller, Joel StevenDinuclear iron(II) complex, [(TPyA)FeII(THBQ 2-)FeII(TPyA)](BF4)2 [TPyA = tris(2-pyridylmethyl)amine; THBQ2- = 2,3,5,6-tetrahydroxy-1,4- benzoquinonate] exhibiting both spin crossover with hysteresis and ferromagnetic exchangeDinuclear [(TPyA)FeII(THBQ22)FeII(TPyA)](BF4)2 (1) possesses hydrogen bonding interactions that form a 1-D chain, and p-p interactions between the 1-D chains that give rise to a 2-D supramolecular-layered structure, inducing hysteresis in the spin crossover behavior; 1 has shown spin crossover behav...Dinuclear complexes2008
267 Miller, Joel Steven[Cyanil]2 2- dimers possess long, two-electron ten-center (2e-/10c) multicenter bondingA long, two-electron ten-center (2e-/10c) [8 carbon plus 2 oxygen] bond in diamagnetic dimers of radical-anion tetracyano-1,4-benzoquinoneide (cyanil, [Q]2 2-, is described by B2LYP and CASSCF92,2)/MCQDPT calculations.Carbon bonds; Cyanil2008
268 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled OsCThe optical spectrum of diatomic OsC has been investigated for the first time, with transitions recorded in the range from 17 390 to 22 990 cm?1. Six bands were rotationally resolved and analyzed to obtain ground and excited state rotational constants and bond lengths. Spectra for six OsC isotopomer...2008
269 Stang, Peter J.Self-selected formation of single discrete supramolecules with flexible, bidentate ligands in the coordination-driven self-assemblyFlexible donor ligands like 1,2-bis(3-pyridyl)ethyne or 1,4-bis(3-pyridyl)-1,3-butadiyne selfassemble into discrete 2-D supramolecules instead of infinite networks upon combination with organoplatinum 90, 120, and 180 degree acceptor units. These systems are unique examples of versatile pyridine...Bidentate ligands; Flexible donor ligands; Supramolecules; Coordination-driven self-assembly2008
270 Miller, Joel StevenStructure of CrIIF(NCMe)2BF4. Rietveld refinement of a component of a physical mixture of unknown compositionThe reaction of CrII(NCMe)4(BF4)2 and [NBun 4][TCNE] (TCNE ¼ tetracyanoethylene) in CH2Cl2 forms a solid that is a mixture of an amorphous reduced-TCNE containing phase(s) and a crystalline component. Rietveld refinement of the high-resolution, synchrotron X-ray powder pattern enabled the determi...Organic-based magnets; Powder X-ray diffraction; Tetracyanoethylene2008
271 Miller, Joel Steven; Epstein, Arthur J.Magnetic bistability and nucleation of magnetic bubbles in a layered 2D organic-based magnet [Fe(TCNE)(NCMe)2][FeC14]The 2D layered organic-based magnet [Fe(TCNE)(NCMe)2][FeCl4] (TCNE ¼ tetracyanoethylene) exhibits a unique macroscopic magnetic bistability between the field-cooled and zero-field-cooled states, which cannot be explained by either superparamagnetic behavior or spin freezing due to spin glass orde...Organic-based magnets; Tetracyanoethylene; Magnetic bistability; Nucleation2008-11
272 Miller, Joel Steven[MeNC5H5]2[TCNE]2 (TCNE = tetracyanoethylene). Single crystal X-ray and neutron diffraction characterization of an exceptionally long 2.8 Å C-C bondThe reaction of N-methylpyridinium iodide, Mepy+I-, and tetracyanoethylene (TCNE) forms [Mepy]2[TCNE]2, which possesses [TCNE]2 2' with an intradimer C-C bond distance of 2.806(1)Å at 50 K from X-ray diffraction, and 2.801(4)Å at 50 K from neutron diffraction. In the IR it exhibits nChN absorption...C-C bond; Tetracyanoethylene; Neutron diffraction; X-ray diffraction; Multicenter C-C bonding2009
273 Armentrout, Peter B.Methane activation by cobalt cluster cations, Con+ (n=2-16): reaction mechanisms and thermochemistry of cluster-CHx (x=0-3) complexesThe kinetic energy dependences of the reactions of Con + (n=2-16) with CD4 are studied in a guided ion beam tandem mass spectrometer over the energy range of 0-10 eV. The main products are hydride formation, ConD+, dehydrogenation to form ConCD2 +, and double dehydrogenation yielding ConC+.Cobalt ions; Transition metal ions; Bond energies; Endothermic reactions; Dehydrogenation; Deuterated methane2009
274 Miller, Joel Steven; Epstein, Arthur J.Direct evidence of electron spin polarization from an organic-based magnet: [FeII(TCNE)(NCMe)2][FeIII Cl4]Direct evidence of an organic-based magnet with a finite electron spin polarization at the Fermi edge is shown from spin-resolved photoemission of the [FeII(TCNE)(NCMe)2][FeIIICl4] organic-based magnet. The 23% majority-based spin polarization at the Fermi edge is observed at 80 K in zero applied fi...Organic-based magnets; Electron spin polarization2009-05
275 Armentrout, Peter B.Infrared multiple photon dissociation spectroscopy of cationized cysteine: effects of metal cation size on gas-phase conformationAbstract The gas-phase structures of cationized cysteine (Cys) including complexes with Li+, Na+, K+, Rb+, and Cs+, as well as protonated Cys, are examined by infrared multiple photon dissociation (IRMPD) action spectroscopy utilizing light generated by a free electron laser, in conjunction with q...2010
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