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CreatorTitleDescriptionSubjectDate
126 Miller, Joel StevenTwo-dimensional molecular-based ferrimamagnets incorporating decamethylmetallocenium cationsFour new molecular-based magnets have been synthesized, and their magnetic properties have been investigated in detail. Their formulae are [M'(C5Me5)2]2M2[Cu(opba)]3.(DMSO)x(H20)y with M' = Fe, M = Mn, x = 5, y = 4 (1), M' = Fe, M = Co, x = 6, y = 4 (2), M' = Co, M = Mn, x = 5.5, y = 4 (3) and M' = ...Magnetic; Compounds1996
127 Miller, Joel StevenCharacterization of novel TCNQ and TCNE 1 : 1 and 1 : 2 salts of the tetrakis(dimethyamino) ethylene dication, [{(CH3)2N}2C-C{N(CH3)2}2]2+Addition of TCNQ to a solution of tetrakis(dimethylamino)ethylene in MeCN produces the salt [TDAE][TCNQ]2; the dipositive cation, [{(CH3)2N}2C-C{N(CH3)2}2]2+, is nonplanar, with a dihedral angle of 63.9(o), while the TCNQ anions crystallize as [TCNQ]2 2- dimers with an interplanar separation of 3.1...Electron; Oxidations; Transfer1996
128 Morse, Michael DavidElectron-spin resonance studies of the titanium cation (Ti+,3d?, ?F) in rare gas matrices at 4 K: A crystal field interpretationElectron-spin resonance studies of laser-ablated titanium metal isolated in neon and argon display an intense feature which exhibits a symmetric, narrow line and a large matrix-dependent g shift. On the basis of a number of experiments, this is assigned to a matrix isolated 3d3,4F Ti+ ion in an octa...1996
129 Miller, Joel Steven; Epstein, Arthur J.Magnetization and dynamics of reentrant ferrimagnetic spin-glass [MnTPP]::+[TCNE].-.2PhMeWe present direct current (dc) magnetization M(T,H) and alternating current (ac) susceptibility Xac(T,H,f) data for the quasi-one-dimensional molecule-based ferrimagnet [MnTPP]::+[TCNE].-.•2PhMe (TPP=meso-tetraphenylporphyrinato, TCNE=tetracyanoethylene). Static scaling of the real part X' of ...Ferrimagnetic order; Magnetism1996
130 Miller, Joel StevenPreparation and characterization of square-planar tetrakis(cyanoacetylide) complexes: [MII(C=C-C=N)4]2- (M = Ni,Pd, Pt)Complexes [MII(C=C-=N)4]2 - (M = Ni, Pd, Pt) are prepared for the first time and the structure of [NEt4]2[Ni(C=C-C=N)4] is determined to have a square-planar geometryBonding; Structure; Ligand1996
131 Morse, Michael DavidResonant two-photon ionization spectroscopy of the 13-electron triatomic Si2NResonant two-photon ionization spectra of 28Si2N, 28,29Si2N, and 28,30Si2N have been collected between 32 000 cm-1 and 36 000 cm-1. A fit of the rotationally resolved spectrum of the most intense band of 28Si2N at 34 314 cm-1 reveals the transition to be 2?+u ? X~ 2IIg,1/2- A molecular orbital analy...1996
132 Stang, Peter J.Supramolecular chemistry and molecular design: self-assembly of molecular squaresModem supramolecular chemistry has been described as organized polymolecular systems held together by noncovalent interactions and represents one of the major frontiers in the chemical sciences.'-' At present the field is dominated by the hydrogen bonding motif that mimics biological systems and th...Molecular design; Molecular squares1997
133 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
134 Miller, Joel Steven; Epstein, Arthur J.Magnetic phase diagram of a molecule-based ferrimagnet: weak ferromagnetism and multiple dimensionality crossoversA detailed study of the magnetic behavior of the molecule-based magnet, [MnOEP][HCBD], (OEP=mesooctaethylporphyrinato, HCBD=hexacyanobutadiene) from 1.7 to 20 K was performed. The earlier reported magnetic transition at 19.6 K, ascribed to a crossover from a one-dimensional Heisenberg-like ferrimag...Transition; Temperature; Magnetization1997
135 Morse, Michael DavidThe bond energy of Rh?In a spectroscopic investigation of jet-cooled Rh2 by the resonant two-photon ionization method, an abrupt predissociation threshold is observed in a dense set of vibronic levels at 19 405?4 cm-1. Based on the high density of states expected in the rhodium dimer, the sharp definition of the prediss...1997
136 Miller, Joel StevenStructure and physical properties of hexacyanomanganate(IV), [MnIV(CN)6]2-Hydrolytically unstable d3 [MnI V(CN)6]2- as the [N(PPh3)2]+ salt is crystallographically, spectroscopically, and magnetically characterized.Absorption; Magnetic; Spin1997
137 Miller, Joel Steven; Epstein, Arthur J.Lattice- and spin-dimensionality crossovers in a linear-chain-molecule-based ferrimagnet with weak spin anisotropy[MnOEP][HCBD], a member of the metalloporphyrin family of donor-acceptor molecule-based magnets, consists of isolated ferrimagnetic chains of alternating S=2, [MnOEP], and s=1/2, [HCBD] units (OEP=octaethylporphyrinato and HCBD=hexacyanobutadiene). Analysis of the exchange pathways reveals an exchan...Magnetic; Magnetization; Interchain1997
138 Morse, Michael DavidOptical spectroscopy of jet-cooled FeC between 12 000 and 18 100 cm-?Iron monocarbide has been investigated between 12 000 and 18 100 cm21 in a supersonic expansion by resonant two-photon ionization spectroscopy. Six new electronic states have been identified for which origins relative to the ground state have been determined. Three of these possess ?"=3, one possess...1997
139 Miller, Joel Steven; Epstein, Arthur J.Effect of disorder on the linear and nonlinear magnetic susceptibilities of two manganeseporphryin-based magnetsWe analyze the effects of disorder on the magnetic properties of two manganeseporphyrins, [MnTPP][TCNE] •. x(o-DCB) and [MnTPP][TCNE] . • y(o-Xy) and (TPP=meso-tetraphenylporphyrinato, TCNE=tetracyanoethylene, o-Xy=o-xylene, o-DCB=o-dichlorobenzene, x<_3,y<_1). We present data for the in- ...Magnetization; Ferrimagnetic; Spins1997
140 Morse, Michael DavidTwo-photon ionization spectroscopy and all-electron ab initio study of LiCaResonant two-photon ionization spectra of LiCa have been obtained from a laser vaporization, supersonic expansion source. The ground state of the molecule is confirmed to be X 2?+. Three band systems have been observed near 15 282, 19 310, and 22 250 cm-1 and the upper states have been assigned as 2...1998
141 Morse, Michael DavidFirst spectroscopic investigation of the 4 d transition metal monocarbide MoCThe first optical spectroscopic investigation of MoC has revealed a complicated vibronic spectrum consisting of about 35 bands between 17 700 and 24 000 cm-1. Analysis has shown the ground state to be the ?=0+ spin?orbit component of a 3?- state that derives from a 10?211?25rr42d 2 configuration. Th...1998
142 Miller, Joel StevenStructure and magnetic properties of MnII[N(CN)2]2(pyrazine). An antiferromagnet with an interpenetrating 3-D network structureMn[N(CN)2]2(pyz) (pyz = pyrazine) orders antiferromagnetically at low temperature and possesses intralayer u-NCNCN and interlayer u-pyz ligands that form a pseudo-ReO3 interpenetrating network structure.Dicyanamide; Polydentate; Temperature1998
143 Miller, Joel StevenInterpenetrating three-dimensional rutile-like frameworks. Crystal structure and magnetic properties of MnII[C(CN)3]2The interpenetrating double-density rutile-like structure and magnetic properties of MnII[C(CN)3]2 are determined.Spin; Bond; Coupling1998
144 Armentrout, Peter B.Guided ion beam studies of the reactions of Crn+ (n=1-18) with CO2: chromium cluster oxide bond energiesThe kinetic energy dependence of the reactions of Crn+ (n=1-18) with CO2 are studied in a guided ion beam mass spectrometer. The primary product ions are CrnO+, which then decompose by sequential loss of chromium atoms as the kinetic energy is increased. Simple collision-induced dissociation to form...Metal clusters; Chromium ions; Oxygen; Bond energies; Exothermic reactions; Endothermic reactions1998
145 Miller, Joel Steven; Epstein, Arthur J.Tetracyanoethylene-based organic magnetsSeveral classes of organic magnets based upon the tetracyanoethenide radical anion, [TCNE](.-), either unbound, (u), and (u4) bonded to zero, two and four metal sites have been reported. The putative (u4) bonded V(TCNE)x room temperature magnet has been extended to include M(TCNE)x(M = Mn, Fe, Co,...Magnetization; Magnetic ordering; Oxidation1998
146 Morse, Michael DavidA pair potentials study of matrix-isolated atomic zinc. II. Intersystem crossing in rare-gas clusters and matricesThe mechanism of 4p 1P1?4p 3PJ intersystem crossing (ISC) following excitation of the 4p 1P1 level of matrix-isolated atomic zinc is investigated using a pair potentials approach. This is achieved by extending earlier ISC calculations on the Zn?RG2 and Zn?RG3 complexes to the square planar Zn?RG4 ...1998
147 Armentrout, Peter B.Guided ion beam studies of the reactions of Crn + (n=2-18) with O2: chromium cluster oxide and dioxide bond energiesThe kinetic energy dependence of the reactions of Crn+ (n=2-18) with O2 are studied in a guided ion beam mass spectrometer. A variety of CrmO2+, CrmO+, and Crm+ product ions, where m≤n, are observed, with the dioxide cluster ions dominating the products for all larger reactant cluster ions. React...Metal clusters; Chromium ions; Oxygen; Oxygen; Bond energies; Exothermic reactions1998
148 Miller, Joel StevenIsolation and structural determination of octacyanobutanediide, [C4(CN)8]2-; precursors to M(TCNE)x magnets(**)The reaction of MI2.xMe3CN (M = Mn, Fe) and TCNE (tetracyanoethylene) leads to unprecedented [C4(CN)8]2-U4-metal complexes which have been crystallographically characterized and are precursors to M(TCNE)x-yS magnets.Absorptions; Magnets; Bond1998
149 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
150 Armentrout, Peter B.Statistical modeling of competitive threshold collision-induced dissociationCollision-induced dissociation of (R1OH)Li+(R2OH) with xenon is studied using guided ion beam mass spectrometry. R1OH and R2OH include the following molecules: water, methanol, ethanol, 1-propanol, 2-propanol, and 1-butanol. In all cases, the primary products formed correspond to endothermic loss of...Collision-induced dissociation; Xenon ions; Alcohols1998
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