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CreatorTitleDescriptionSubjectDate
201 Truong, Thanh; Sarofim, Adel F.Quantum mechanic study of high molecular mass compounds in combustion conditionsExperimental studies on soot formation show interesting trends that can only be explained by a polymerization pathway. These experimental findings are reviewed and ab initio calculations are used to evaluate possible mechanistic pathways. A sequence of chemical reactions between aromatic compounds a...High molecular mass compounds; Quantum mechanics; Soot formation2001
202 Miller, Joel Steven; Epstein, Arthur J.Quest for a polymeric ferromagnet: a new polymorph of 1,4-bis(2,2,6,6-tetramethyl-4-oxy-4-piperidyl-1-oxy)butadiyne (invited)A new polymorph of 1,4-bis(2,2,6,6-tetramethyl-4-oxy-4-piperidyl-l-oxy) butadiyne has been prepared and characterized by x-ray diffraction, infrared and Raman spectroscopies, and magnetic susceptibility. Unlike t h e Pccn-a phase, the B phase belongs to the Pca2y1 space group [a = 14.265(1) A(o),b ...Molecular; Magnetic; Thermal1988
203 Miller, Joel Steven; Epstein, Arthur J.Quest for molecule-based magnetsIn the past decade a new class of magnets possessing spins on organic species have been discovered and studied. These magnets can be fabricated at room temperature and may enable useful devices and/or processes. Herein we discuss several of the mechanisms that can enable the stabilization of magn...Mechanisms; Ferromagnetic; Spin coupling1996
204 Truong, ThanhReaction class transition state theory: hydrogen abstraction reactions by hydrogen atoms as test casesWe present a new method called Reaction Class Transition State Theory (RC-TST) for estimating thermal rate constants of a large number of reactions in a class. This method is based on the transition state theory framework within the reaction class approach. Thermal rate constants of a given reacti...Transition state theory; Hydrogen2000
205 Armentrout, Peter B.Reaction of Cr+, Mn+, Fe+, Co+, and Ni+ with O2 and N2O. Examination of the translational energy dependence of the cross sections of endothermic reactionsReactions of Cr+, Mn+, Fe+, Co+, and Ni+ with 02 and N20 to yield metal oxide ions are examined using an ion beam apparatus. Reaction cross sections a as a function of ion translational energy E are reported. With one exception, Fe+ + N20, the cross sections exhibit an energy threshold E0.Metal oxides; Endothermic reactions; Translational energy; Bond energy; Threshold energy1982
206 Armentrout, Peter B.Reaction of Cu+ with dimethoxyethane: competition between association and multiple dissociation channelsThe reaction of Cu1 with dimethoxyethane (DXE) is studied using kinetic-energy dependent guided ion beam mass spectrometry. The bimolecular reaction forms an associative Cu1(DXE) complex that is long-lived and dissociates into several competitive channels: C4H9O2 11CuH, Cu1(C3H6O)1CH3OH, back to rea...Dimethoxyethane; Copper ions; Association reactions; Collision-induced dissociation; Phase state theory2004
207 Armentrout, Peter B.Reactions of Ar+, Ne+, and He+ with SiF4 from thermal energy to 50 eV c.m.Guided ion-beam techniques are used to measure the cross sections for reaction of SiF4 with Ar+, Ne+, and He+ from thermal to 50 eV. Charge transfer followed by loss of F atoms are the sole processes observed. All SiFx + (x = 0-4) products are observed, except for SiF4 + from reaction with Ne+ and ...Ion-molecule reactions; Tetrafluorosilane; Rare gas ions; Endothermic reactions; Plasma systems1989
208 Armentrout, Peter B.Reactions of Pt+ with H2, D2, and HD: effect of lanthanide contraction on reactivity and thermochemistryA guided ion beam tandem mass spectrometer is used to examine the kinetic energy dependence of reactions of the third-row transition metal cation, Pt1, with molecular hydrogen and its isotopologs. A flow tube ion source produces Pt1 ions in its electronic ground state term and primarily in the lowes...Metal clusters; Platinum ions; Lanthanide contraction; Bond energies; Endothermic reactions; Transition metal ions; Dihydrogen2002
209 Armentrout, Peter B.Reactions of Ta+ and W+ with H2, D2, and HD: effect of lanthanide contraction and spin-orbit interactions on reactivity and thermochemistryA guided ion beam tandem mass spectrometer is used to examine the kinetic energy dependence of reactions of the third-row transition metal cations, Ta1, and W1, with molecular hydrogen and its isotopologs. A flow tube ion source produces Ta1 and W1 ions in their electronic ground state term and p...Metal clusters; Tantalum ions; Tungsten ions; Lanthanide contraction; Bond energies; Endothermic reactions; Transition metal ions; Dihydrogen2002
210 Armentrout, Peter B.Reactions of Ta+, W+, and Pt+ with H2, D2, and HD: effect of lanthanide contraction and spin-orbit interactions on reactivity and thermochemistryThere have been extensive experimental studies of the reactions of atomic first-row and second-row transition metal cations with dihydrogen and its isotopic analogues in our group. For third-row transition metal cations, however, only La+ and Lu+ systems have been studied experimentally although t...Lanthanide contraction; Spin-Orbit interactions; Reactivity2002
211 Miller, Joel Steven; Epstein, Arthur J.; Zhang, JieReentrance in the Mn(tetracyanoethylene)x.y(CH2Cl2) high-Tc molecule-based ferrimagnetResults of static and dynamic magnetic studies of the compound Mn(TCNE)x•y(CH2Cl2) (TCNE =tetracyanoethylene) are reported. Curie-Weiss analysis of the high-temperature susceptibility data indicates a relatively strong exchange. The ac susceptibility, measured as a function of frequency and tempe...Transition; Reentrant; Magnetic1998
212 Armentrout, Peter B.Relative and absolute bond dissociation energies of sodium cation-alcohol complexes determined using competitive collision-induced dissociation experimentsAbsolute (R1OH)Na+-(R2OH) and relative Na+-(ROH) bond dissociation energies are determined experimentally by competitive collision-induced dissociation of (R1OH)Na+(R2OH) complexes with xenon in a guided ion beam mass spectrometer. The alcohols examined include ethanol, 1-propanol, 2-propanol, n-but...2010
213 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
214 Morse, Michael DavidResonant two-photon ionization spectroscopy of LiCuJet-cooled LiCu has been investigated using resonant two-photon ionization spectroscopy. A long vibrational progression was observed and identified as the [20.5] 1?+? X 1?+ band system. Ten bands of the system were rotationally resolved for 7Li63Cu, giving bond lengths of r0=2.2618(3) ? for the X 1?...1997
215 Morse, Michael DavidResonant two-photon ionization spectroscopy of NiCA spectroscopic investigation of jet-cooled diatomic NiC has revealed a complex pattern of vibronic levels in the wave number range from 21 700 to 27 000 cm-1. Of the more than 50 vibronic bands observed, 31 have been rotationally resolved and analyzed. All are ?'=0+??"=0+ transitions, consistent wi...2002
216 Morse, Michael DavidResonant two-photon ionization spectroscopy of coinage metal trimers: Cu?Ag, Cu?Au, and CuAgAuThe jet-cooled coinage metal triatomic molecules Cu, Ag, Cu, Au, and CuAgAu have been investigated using resonant two-photon ionization spectroscopy. One band system, labeled as the ?-x system, has been observed for each species, with origin bands at 13 188, 17 217, and 17 470 cm -?, respectively. ...1991
217 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled Au?A band system of jet-cooled Au, has been located in the near infrared region of the spectrum using resonant two-photon ionization spectroscopy. The origin band is located at 13 354.15 cm-? and the system extends more than 700 cm-? further to the blue. The excited state displays a radiative lifetime...1991
218 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled NiPtResonant two-photon ionization spectroscopy of jet-cooled NiPt has been used to investigate the possibility of <f-electron contributions to the bonding in this species. Based on an abrupt onset of predissociation, the bond strength of NiPt is assigned as D0 (NiPt) = 2.798 ? 0.003 eV. Comparisons of ...1989
219 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
220 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled OsN: 520?418 nmThe optical transitions of supersonically cooled OsN have been investigated in the range from 19 200 to 23 900 cm?1 using resonant two-photon ionization spectroscopy. More than 20 vibronic bands were observed, 17 of which were rotationally resolved and analyzed. The ground state is confirmed to be 2...2011
221 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled PdCThe first optical investigation of the spectra of diatomic PdC has revealed that the ground state has ?=0+, with a bond length of r0=1.712?. The Hund?s case (a) nature of this state could not be unambiguously determined from the experimental data, but dispersed fluorescence studies to be reported in...1999
222 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled PdSiThe spectra of diatomic PdSi have been investigated for the first time, using the technique of resonant two-photon ionization spectroscopy. A number of vibronic transitions have been observed in the 20 400?22 000 cm?1 range. It is difficult to group the bands into band systems, although one likely...2011
223 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled Pt?The gas phase optical spectrum of jet-cooled Pt? has been investigated over the range of 11 300 to 26 300 cm -1 using resonant two-photon ionization spectroscopy in combination with time-of-flight mass spectrometry. Numerous vibronic bands are observed. Analysis of the data gives the location of som...1988
224 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled PtSiJet-cooled diatomic PtSi, produced in a laser ablation supersonic expansion source, has been spectroscopically investigated between 17 400 and 24 000 cm-1 by resonant two-photon ionization spectroscopy. Two vibrational progressions are observed and identified as the [15.7]?'=1 ?X 1?+ and [18.5]?'=1 ...1999
225 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled RuCA resonant two-photon ionization study of the jet-cooled RuC molecule has identified the ground state as a 1?+ state arising from the 10?211?25rr42?4 configuration. The 3?i state arising from the 10?211?25rr42?312?1 configuration lies very low in energy, with the 3?3 and 3?2 components lying only 76...1998
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