TY - CONF TI - The Effects of Aromaticity and Reduced Bond Length Alternation on Linear and Third-Order Polarizabilities on Conjugated Organic Chromophores AU - Gorman, C.B. AU - Marder, S.R. C2 - 1993/// C3 - Proceedings of the Materials Research Society DA - 1993/// VL - 291 SP - 579–584 PB - Soc ER - TY - JOUR TI - An Investigation of the Interrelationships between Linear Polarizability, First and Second Hyperpolarizabilities and Bond Length Alternation in Conjugated Donor-Acceptor Compounds AU - Gorman, C.B. AU - Marder, S.R. T2 - Proceedings of the National Academy of Science DA - 1993/// PY - 1993/// VL - 90 SP - 11297–11301 ER - TY - CONF TI - Optimization of the First and Second Hyperpolarizabilities of Organic Dyes AU - Bourhill, G.H. AU - Brédas, J.L. AU - Cheng, L.-T. AU - Friedli, A.C. AU - Gorman, C.B. AU - Marder, S.R. AU - Meyers, F. AU - Perry, J.W. AU - Pierce, B.M. AU - Skindhøj, J. AU - Tiemann, B.G. T3 - Technical Digest Series (Optical Society of America) C2 - 1993/// C3 - Organic thin films for photonic applications : summaries of papers presented at the Organic Thin Films for Photonic Applications Topical Meeting DA - 1993/// SP - 46 PB - Optical Society of America ER - TY - JOUR TI - Pathway of H2 Desorption from Dihydride Si(100) AU - Jing, Z. AU - Whitten, J.L. T2 - Physical Review B AB - In the present paper, the pathway of ${\mathrm{H}}_{2}$ desorption from a dihydride species -${\mathrm{SiH}}_{2}$ on the Si(100) surface, -${\mathrm{SiH}}_{2}$\ensuremath{\rightarrow}-Si+${\mathrm{H}}_{2}$ (-Si represents a surface Si atom site), is investigated. This pathway involves the recombination of two H atoms bonded to the same surface silicon atom. A three-layer cluster that consists of 12 silicon atoms and 20 hydrogen saturators is used to simulate the Si(100) surface and ab initio self-consistent-field and configuration-interaction theory is used to treat the cluster and desorption reactions. With the correction of zero-point vibrational energies, the ${\mathrm{H}}_{2}$ desorption energy and activation barrier are computed to be 48 and 53 kcal/mol, respectively. The corresponding adsorption barrier is 5 kcal/mol. Considering the experimental uncertainty and the uncertainty of our calculations, we conclude that the barrier of ${\mathrm{H}}_{2}$ desorption from the dihydride surface via -${\mathrm{SiH}}_{2}$ is consistent with the experimental result. DA - 1993/12/15/ PY - 1993/12/15/ DO - 10.1103/PhysRevB.48.17296 VL - 48 IS - 23 SP - 17296 ER - TY - CONF TI - Chemical Modification of Surface Steps on Si(111) Vicinal Wafers: A Bonding Model for Phase Changes in Second Harmonic Generation AU - Jing, Z. AU - Lucovsky, G. AU - Whitten, J.L. C2 - 1993/// C3 - MRS Online Proceedings Library DA - 1993/// DO - 10.1557/PROC-318-287 VL - 318 SP - 287-292 ER - TY - RPRT TI - Fundamental studies of defect generation in amorphous silicon alloys grown by remote plasma-enhanced chemical-vapor deposition (Remote PECVD) Annual Subcontract Report 1 September 1990 - 31 August 1991 AU - Lucovsky, G. AU - Nemanich, R.J. AU - Bernholc, J. AU - Whitten, J. AU - Wang, C. AU - Davidson, B. AU - Williams, M. AU - Lee, D. AU - Bjorkman, C. AU - Jing, Z. A3 - National Renewable Energy Laboratory AB - We demonstrated that the remote PECVD process can be used to deposit heavily doped n-type and p-type a-Si:H thin films. We optimized conditions for depositing undoped, near-intrinsic and heavily doped thin films of [mu]c(microcrystalline)-Si by remote PECVD. We extended the remote PECVD process to the deposition of undoped and doped a-Si,C:H and [mu]c-Si,C alloy films. We analyzed transport data for the dark conductivity in undoped and doped a-Si:H, a-Si,C:H, [mu]c-Si and [mu]c-Si,C films. We studied the properties of doped a-Si:H and [mu]c-Si in MOS capacitors using [approximately]10 [Omega]-cm p-type crystalline substrates and thermally grown Si0[sub 2] dielectric layers. We collaborated with a group at RWTH in Aachen, Germany, and studied the contributions of process induced defect states to the recombination of photogenerated electron pairs. We applied a tight-binding model to Si-Bethe lattice structures to investigate the effects of bond angle, and dihedral angle disorder. We used ab initio and empirical calculations to study non-random bonding arrangements in a-Si,O:H and doped a-Si:H films. C6 - NREL/TP-451-4852 DA - 1993/1/1/ PY - 1993/1/1/ DO - 10.2172/6796766 M1 - NREL/TP-451-4852 PB - National Renewable Energy Laboratory SN - NREL/TP-451-4852 ER - TY - JOUR TI - Mechanism of H2 desorption from monohydride Si(100)2 × 1H AU - Jing, Z. AU - Lucovsky, G. AU - Whitten, J.L. T2 - Surface Science AB - Most recent experimental work on H2 desorption from the monohydride Si(100) surface seems to point to a pairwise desorption mechanism involving the concerted desorption of two hydrogen atoms on different Si atoms of a single dimer. Using ab initio SCF and CI theory and a cluster model of the surface, the present work finds that the lowest energy pathway is symmetric rather than asymmetric. The desorption energy barrier is calculated to be 3.7 eV. Compared with an experimental value of 2.6 eV, the large barrier suggests that this direct desorption mechanism is not applicable. A multi-step desorption mechanism which involves a delocalized process in the formation of dihydride SiH2 and a localized desorption of H2 is proposed and is shown to explain the experimental observations. DA - 1993/11// PY - 1993/11// DO - 10.1016/0039-6028(93)90022-c VL - 296 IS - 3 SP - L33-L37 J2 - Surface Science LA - en OP - SN - 0039-6028 UR - http://dx.doi.org/10.1016/0039-6028(93)90022-c DB - Crossref ER - TY - JOUR TI - Reaction of CH4 with substitutional Fe/Ni(111) AU - Hong, Yang AU - Whitten, Jerry L. T2 - Surface Science AB - The reaction of CH4 with a substitutional Fe/Ni(111) surface is treated using a many-electron embedding theory, modelling the lattice as a 41-atom, three layer cluster. Ab initio valence orbital configuration interaction (multiple parent) calculations carried out on a local surface region permit an accurate description of bonding at the surface. The 3d orbitals are explicitly used for the Fe atom and six nearest neighbor Ni atoms in the local surface region. The calculated activation energy for CH4 dissociation at an atop Fe site to produce CH3 and H coadsorbed on the surface is 5.7 kcal/mol, compared with 16.7 kcal/mol on Ni(111). The reaction of CH4 → CH3(ads) + H(ads) is predicted to be 4 kcal/mol exothermic on the Fe/Ni(111) surface and the immediate dissociation products are CH3 and H coadsorbed at across atom three-fold sites. Across bond dissociation is energetically very unfavorable. The bonding properties of coadsorbed CH3 and H on the Fe/Ni(111) surface are similar to those on the Ni(111) surface. Compared to the clean Ni(111), the substitutional Fe/Ni(111) surface is very effective in activating CH4. DA - 1993/5// PY - 1993/5// DO - 10.1016/0039-6028(93)90885-n VL - 289 IS - 1-2 SP - 30-38 J2 - Surface Science LA - en OP - SN - 0039-6028 UR - http://dx.doi.org/10.1016/0039-6028(93)90885-n DB - Crossref ER - TY - JOUR TI - Theoretical studies of H2 desorption from Si(100)–2×1H AU - Jing, Z. AU - Whitten, J. L. T2 - The Journal of Chemical Physics AB - Theoretical studies of H2 desorption from a cluster model of the Si(100)–2×1H surface show that the desorption pathway is symmetrical and has a desorption energy barrier of 3.75 eV and a corresponding adsorption energy barrier of 1.15 eV. The proper treatment of electron correlation lowers the desorption energy barrier considerably. The present results suggest that the desorption of two hydrogen atoms from different Si atoms of a surface dimer is not the desorption pathway observed experimentally at activation energies in the range 2.0–2.9 eV. DA - 1993/5// PY - 1993/5// DO - 10.1063/1.464685 VL - 98 IS - 9 SP - 7466-7470 J2 - The Journal of Chemical Physics LA - en OP - SN - 0021-9606 1089-7690 UR - http://dx.doi.org/10.1063/1.464685 DB - Crossref ER - TY - JOUR TI - Theoretical studies of surface reactions: embedded cluster theory AU - Whitten, J.L. T2 - Chemical Physics AB - A theoretical approach to the description of the electronic structure of molecules adsorbed on solid surfaces and surface reactions is described. The objective is a quantitative, molecular level, understanding of surface processes, including chemisorption energetics, adsorbate structure and reaction mechanisms. The electronic structure problem is formulated as an embedded cluster of atoms in which a localization transformation is used to define the electronic subspace that interacts strongly with the adsorbate and surface region. This permits ab initio SCF and CI calculations of molecular quality to be performed on a portion of the lattice—adsorbate system. Assumptions of the theory are discussed and applications to chemisorption on transition metal substrates are referenced. DA - 1993/11// PY - 1993/11// DO - 10.1016/0301-0104(93)80020-a VL - 177 IS - 2 SP - 387-397 J2 - Chemical Physics LA - en OP - SN - 0301-0104 UR - http://dx.doi.org/10.1016/0301-0104(93)80020-a DB - Crossref ER - TY - JOUR TI - Effects of subsurface Na, H and C on the bonding of carbon to nickel surfaces AU - Yang, Hong AU - Whitten, Jerry L. AU - Markunas, Robert J. T2 - Surface Science Letters AB - This paper reports the results of a theoretical study of Na, H and C subsurface atomic species in nickel and demonstrates how these interstitial atoms influence the reactivity of the Ni(111) surface and the structure of carbon species adsorbed on the surface. The benzene molecule, C6H6, in planar and nonplanar geometries, is used to probe bonding at the surface. Adsorption energies are calculated by ab initio configuration techniques modelling the surface as an embedded cluster. Adsorption energies of planar C6H6 at the most stable, three-fold, adsorption site are 18 kcal/mol for the Ni(111) surface, and 10, 19 and 44 kcal/mol in the presence of the Na, H and C interstitials, respectively. The energies required for the planar to puckered distortion are 99 kcal/mol on Ni(111), 69 kcal/mol with the Na interstitial, 83 kcal/mol with H, and 134 kcal/mol with C compared to 198 kcal/mol for distortion of C6H6 in the gas phase. The possible relevance of these results to the nucleation of diamond on nickel are discussed. The results indicate that subsurface Na stabilizes tetrahedrally bonded carbon subunits of the diamond structure while subsurface C may make it easier for the overlayer to revert to a planar graphite structure. DA - 1993/9// PY - 1993/9// DO - 10.1016/0167-2584(93)91086-4 VL - 294 IS - 3 SP - L945-L951 J2 - Surface Science Letters LA - en OP - SN - 0167-2584 UR - http://dx.doi.org/10.1016/0167-2584(93)91086-4 DB - Crossref ER - TY - JOUR TI - Dissociative adsorption of H2 on Ni(111) AU - Yang, Hong AU - Whitten, Jerry L. T2 - The Journal of Chemical Physics AB - Ab initio configuration interaction calculations are performed to study the dissociative adsorption of H2 on a Ni(111) surface. The lattice is modeled as an embedded three-layer 41-atom cluster. Ni 3d orbitals are explicitly included on seven Ni atoms on the surface. H is preferentially chemisorbed at a threefold site on Ni(111) and the calculated binding energy of 62 kcal/mol, H–Ni distance of 1.86 Å, and H vibrational frequency of 1176 cm−1 are in excellent agreement with experimental data. H adsorbed at bridge and on-top Ni sites is 2.5 and 8.1 kcal/mol less stable, respectively. The heat of reaction H2 (gas)→2 H (ads) is calculated to be 22.0 kcal/mol exothermic. When two H atoms are adsorbed as nearest neighbors to the same Ni atom, threefold sites are preferred with H atoms adsorbed at fcc–fcc, hcp–hcp, or across atom fcc–hcp sites. These structures are consistent with the observed (2×2)−2H low energy electron diffraction pattern. The average adsorption energy per H is calculated to be 62 kcal/mol for the across atom case. Adsorption of H at a threefold site on Ni(111) has a tendency to block adsorption at adjacent threefold sites; coadsorbed H atoms at adjacent sites are unbound by 13.5 kcal/mol relative to H2 at infinite separation. For three H atoms chemisorbed at separated threefold sites sharing a Ni atom with the equal H–H lateral distances of 2.48 Å, the calculated average adsorption energy is 60 kcal/mol per H. Dissociation of H2 at an on-top Ni site has the lowest activation barrier of 1.6 kcal/mol. For the transition state, the H–H bond length, H-surface height, and H–H vibrational frequency are 1.22 Å, 1.38 Å, and 2506 cm−1, respectively. Molecular H2 adsorbed over an on-top site is bound by 3.4 kcal/mol with a slightly stretched H–H bond length of 0.79 Å, H-surface height of 1.85 Å, and H–H stretching frequency of 3396 cm−1. DA - 1993/3/15/ PY - 1993/3/15/ DO - 10.1063/1.464958 VL - 98 IS - 6 SP - 5039-5049 J2 - The Journal of Chemical Physics LA - en OP - SN - 0021-9606 1089-7690 UR - http://dx.doi.org/10.1063/1.464958 DB - Crossref ER - TY - JOUR TI - Evaluation of potential ferromagnetic coupling units: the bis(TMM) bis(trimethylenemethane)] approach to high-spin organic molecules AU - Jacobs, S.J. AU - Shultz, D.A. AU - Jain, R. AU - Novak, J. AU - Dougherty, D.A. T2 - Journal of the American Chemical Society AB - ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEvaluation of potential ferromagnetic coupling units: the bis(TMM) [bis(trimethylenemethane)] approach to high-spin organic moleculesS. Joshua Jacobs, David A. Shultz, Rakesh Jain, Julie Novak, and Dennis A. DoughertyCite this: J. Am. Chem. Soc. 1993, 115, 5, 1744–1753Publication Date (Print):March 1, 1993Publication History Published online1 May 2002Published inissue 1 March 1993https://doi.org/10.1021/ja00058a020RIGHTS & PERMISSIONSArticle Views410Altmetric-Citations71LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. 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Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (1 MB) Get e-Alerts Get e-Alerts DA - 1993/// PY - 1993/// DO - 10.1021/ja00058a020 VL - 115 IS - 5 SP - 1744–1753 ER - TY - CONF TI - Preparation of meso-Tetra(4-galvinolphenyl)porphyrin — A Building Block for Molecular Magnetic Materials AU - Schultz, D T2 - National ACS Meeting C2 - 1993/// CY - Chicago, Illinois DA - 1993/// PY - 1993/8/22/ ER - TY - CONF TI - Macrocyclic Tetrapyrrole Assemblies as Building Blocks for Molecular Magnetic Materials AU - Schultz, D T2 - NC Sectional ACS Meeting C2 - 1993/// CY - North Carolina State University, Raleigh, NC DA - 1993/// PY - 1993/3/26/ ER - TY - CONF TI - Protein Monolayer Electrochemistry: A Strategy for Probing Biological Electron Transfer Kinetics AU - Bowden, E.F. AU - Clark, R.A. AU - Willit, J.L. AU - Song, S. T2 - Fifth International Symposium on Redox Mechanisms and Interfacial Properties of Molecules of Biological Importance A2 - Schultz, F. A2 - Taniguchi, I. T3 - Proceedings / Electrochemical Society C2 - 1993/// C3 - Proceedings of the Fifth International Symposium on Redox Mechanisms and Interfacial Properties of Molecules of Biological Importance, 1993 CY - Honolulu, Hawaii DA - 1993/// PY - 1993/5/16/ SP - 34–45 PB - The Electrochemical Society ER - TY - JOUR TI - Preparation of meso-tetra(4-galvinolphenyl)porphyrin—A building block for molecular magnetic materials AU - Shultz, David A. AU - Knox, David A. AU - Morgan, Larry W. AU - Sandberg, Kay AU - Tew, Gregory N. T2 - Tetrahedron Letters AB - The synthesis and oxidative electrochemistry of a free-radical substituted metalloporphyrin are described. The porphyrin is prepared in four steps in good yield. Oxidation at a platinum electrode shows the molecule undergoes five reversible one-electron transfers to a stable pentaradical. DA - 1993/6// PY - 1993/6// DO - 10.1016/s0040-4039(00)60593-2 VL - 34 IS - 25 SP - 3975-3978 J2 - Tetrahedron Letters LA - en OP - SN - 0040-4039 UR - http://dx.doi.org/10.1016/s0040-4039(00)60593-2 DB - Crossref ER - TY - JOUR TI - Two new structural types for d3-d3 dimers of molybdenum and tungsten: [K(18-crown-6)]+[Mo2(OCH2But)7]- and [W2{P(c-hexyl)2}3(OCH2But)3{HP(c-hexyl)2}] AU - Budzichowski, T.A. AU - Chisholm, M.H. AU - Martin, J.D. AU - Huffman, J.C. AU - Moodley, K.G. AU - Streib, W.E. T2 - Polyhedron AB - Abstract The syntheses and structures (determined by single-crystal X-ray diffraction techniques) are reported for [K(18-crown-6)]+[Mo2(OCH2But)7]− and [W2{P(c-hexyl)3}3(OCH2But3{HP(c-hexyl)2}]. The former contains a single bridging (μ-OCH2But) ligand, six terminal alkoxide ligands and an MM triple bond. The latter contains three bridging (μ-PR2) ligands and an MM bond distance that is most consistent with the presence of a single bond. These two compounds are the first examples of M2L7 complexes with bridging ligands. They highlight the delicate balance of metal-metal vs metal-ligand bonding in the coordination chemistry of d3-d3 dimers of molybdenum and tungsten. DA - 1993/// PY - 1993/// DO - 10.1016/S0277-5387(00)81733-7 VL - 12 IS - 3 SP - 343-345 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-1842778695&partnerID=MN8TOARS ER - TY - JOUR TI - A tetranuclear tungsten carbido alkoxide cluster with a hydride ligand: W4(μ-C)(NMe)(OCH2But)11(H) AU - Chisholm, M.H. AU - Johnston, V. AU - Martin, J.D. AU - Lobkovsky, E. AU - Huffman, J.C. T2 - Journal of Cluster Science DA - 1993/// PY - 1993/// DO - 10.1007/BF00702712 VL - 4 IS - 2 SP - 105-117 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33748533735&partnerID=MN8TOARS ER - TY - JOUR TI - [Et3PH][W4O3Cl7(PEt3)3]. A 12-electron tetrahedral tungsten cluster with an interesting arrangement of ligands AU - Barry, J.T. AU - Chacon, S.T. AU - Chisholm, M.H. AU - Folting, K. AU - Martin, J.D. T2 - Journal of Cluster Science DA - 1993/// PY - 1993/// DO - 10.1007/BF00703742 VL - 4 IS - 3 SP - 259-269 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-34250081873&partnerID=MN8TOARS ER - TY - JOUR TI - Triple bonds between tungsten atoms with ancillary dimesitylboroalkoxide ligands. Preparations, properties and structures of W2(NMe2)4[OB(Mes)2]2 and W2(OBut)4[OB(Mes)2]2 AU - Chisholm, M.H. AU - Folting, K. AU - Haubrich, S.T. AU - Martin, J.D. T2 - Inorganica Chimica Acta AB - From the reaction between W2(NMe2)6 and dimesitylborinic acid, (Mes)2BOH (2 equiv.), in toluene, the golden- yellow crystalline compound W2(NMe2)4[OB(Mes)2]2 (1) has been isolated and characterized (elemental analysis, 1H, 13C{1H}, 11B NMR spectroscopy, IR spectroscopy and a single crystal X-ray diffraction study). At −160 °C, a=39.379(7), b=13.649(2), c=21.918(4) Å, β=123.12(1)°, Z=8 and space group C2/c. The compound W2(OBut)4[OB(Mes)2]2 (2) has been similarly characterized as a dark red crystalline compound obtained from the reaction between W2(OBut)6 and (Mes)2BOH (2 equiv.) in toluene. At −159 °C, a=17.164(2), b=19.773(2), c=18.490(2) Å, β=102.91(1)°, Z=4 and space group C2. In both compounds there are unsupported WW bonds of distance 2.3068(13) and 2.3521(15) Å for compound 1 and 2, respectively. In 1 there is a central ethane like W2N4O2 core with the gauche conformation, WN=1.94(2) (av.) and WO=1.93(1) Å. The coordination geometry at nitrogen is trigonal planar and the NC2 units are aligned along the WW axis as found for related compounds. In compound 2 the W2O4O′2 skeleton is eclipsed and most surprisingly the WO′ distances to the OB(Mes)2 ligands are shorter 1.81(1) Å than the WO distances 1.94(1) and 1.90(1) Å to the alkoxide ligands. In both 1 and 2 the coordination geometry at boron is trigonal planar and the OB distances fall in the range 1.37(3)–1.41(3) Å, and are statistically equivalent to that of the free borinic acid. Compound 2 has crystallographically imposed C2 symmetry and the OB(Mes)2 groups are syn. These are the first structurally characterized boroalkoxides coordinated to the (WW)6+ moiety and comparisons of WO π bonding are made with respect to related OR and OSiR3 compounds. DA - 1993/// PY - 1993/// DO - 10.1016/S0020-1693(00)83809-8 VL - 213 IS - 1-2 SP - 17-24 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0013399462&partnerID=MN8TOARS ER - TY - JOUR TI - Doubly-hydrated hexafluoroacetylacetone as a tetradentate ligand: Synthesis, magnetochemistry, and thermal transformations of a MnIII 2 complex AU - Bouwman, E. AU - Caulton, K.G. AU - Christou, G. AU - Folting, K. AU - Gasser, C. AU - Hendrickson, D.N. AU - Huffman, J.C. AU - Lobkovsky, E.B. AU - Martin, J.D. AU - Michel, P. AU - Tsai, H.-L. AU - Xue, Z. T2 - Inorganic Chemistry DA - 1993/// PY - 1993/// VL - 32 IS - 16 SP - 3463-3470 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0001208732&partnerID=MN8TOARS ER - TY - JOUR TI - A comparison of heterometallic alkoxide molecules containing copper(I) or copper(II) and zirconium AU - Vaartstra, B.A. AU - Samuels, J.A. AU - Barash, E.H. AU - Martin, J.D. AU - Streib, W.E. AU - Gasser, C. AU - Caulton, K.G. T2 - Journal of Organometallic Chemistry AB - The synthesis, characterization and structure and thermal decomposition of ClCuIIZr2(OiPr)9 (1) and Cu2IZr2(OiPr)10 (2) are reported. Compound 1 has a CuZr2(μ3-OR)2(μ2-OR)3 central core, with chloride as a terminal ligand on copper. This paramagnetic CuII species is particularly interesting in that the 1H NMR signals of those alkoxides which are μ2- and μ3-bridged to copper undergo paramagnetic shifts (to 8.66 and 10.41 ppm at 25°C), but those of the remaining alkoxide groups are unperturbed from the region characteristic of the Zr2(OiPr)9− unit. Compound 2 consists of a Zr2(OiPr)9− face-sharing bioctahedron with two μ2-alkoxides bridging to a Cu2IOR+ fragment giving the copper a linear two-coordinate environment. Both 1 and 2 are highly soluble in hydrocarbon solvents. TGA studies of both compounds reveal information on possible mechanisms and products of thermolysis. DA - 1993/// PY - 1993/// DO - 10.1016/0022-328X(93)80123-S VL - 449 IS - 1-2 SP - 191-201 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0006936601&partnerID=MN8TOARS ER - TY - JOUR TI - Structural and electronic study of donors composed of two TTF moieties linked by tellurium bridges AU - Martin, J.D. AU - Canadell, E. AU - Becker, J.Y. AU - Bernstein, J. T2 - Chemistry of Materials DA - 1993/// PY - 1993/// VL - 5 IS - 9 SP - 1199-1203 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0000673352&partnerID=MN8TOARS ER - TY - JOUR TI - Carbon-carbon coupling of a μ-ethynyl ligand with an isocyanide at a ditungsten center. Preparation and structure of W2(μ-CCCNHXyl)(OSiMe2BUt) 5(CNXyl)4, where Xyl = 2,6-Me2C6H3 AU - Chisholm, M.H. AU - Cook, C.M. AU - Huffman, J.C. AU - Martin, J.D. T2 - Organometallics DA - 1993/// PY - 1993/// VL - 12 IS - 6 SP - 2354-2359 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0011476262&partnerID=MN8TOARS ER - TY - JOUR TI - A new vanadium(V) persulfide complex: (NEt4)[VO(S2)2(bpy)] AU - Castro, S.L. AU - Martin, J.D. AU - Christou, G. T2 - Inorganic Chemistry DA - 1993/// PY - 1993/// VL - 32 IS - 13 SP - 2978-2980 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0000312966&partnerID=MN8TOARS ER - TY - CONF TI - Third-order polarizabilities of symmetric and nonsymmetric polyene and cyanine-like organic molecules AU - Bourhill, Grant AU - Mansour, Kamjou AU - Tiemann, Bruce G. AU - Gorman, Christopher B. AU - Biddle, Shawnna AU - Marder, Seth R. AU - Perry, Joseph W. T2 - OE/LASE'93: Optics, Electro-Optics, & Laser Applications in Science& Engineering A2 - Rentzepis, Peter M. AB - The second hyperpolarizability, (gamma) , of the donor-acceptor polyene compounds (CH3)2N-(CHequalsCH)3-CHO, 3, (CH3CH2CH2CH2)2N- (CHequalsCH)2-CHequalsC(CN)2, 4, the cyanine compound [CH2CH2OCH2CH2-N-(CHequalsCH)3-CHequalsN-CH2CH2OCH2CH2]+ClO4-, 5, and the linear polyenes CH3- (CHequalsCH)n-CH3, where n equals 4, 1, or 5, 2, have been measured by third harmonic generation (THG) at 1907 nm, in a series of solvents ranging in polarity from CCl4 to CH3OH. It was found that 3, with the moderately strong formyl acceptor, had positive values of (gamma) which exhibit a peak as a function of solvent polarity. In contrast, 4, with the stronger dicyanovinyl acceptor, had positive (gamma) in very nonpolar solvents but increasingly negative (gamma) values in solvents of moderate to high polarity. These solvent- dependent hyperpolarizabilities are associated with a change in geometry from a highly bond length alternated, polyene-like structure for the formyl-substituted compound in nonpolar solvents, to a cyanine-like structure, with very little bond length alternation, for the dicyanovinyl-substituted compound in polar solvents. C2 - 1993/4/27/ C3 - Organic and Biological Optoelectronics DA - 1993/4/27/ DO - 10.1117/12.144063 PB - SPIE UR - http://dx.doi.org/10.1117/12.144063 DB - Crossref ER - TY - JOUR TI - Hydroxyl radical production in the reactions of copper-containing amine oxidases with substrates AU - Castellano, F.N. AU - He, Z. AU - Greenaway, F.T. T2 - BBA - General Subjects AB - Solutions of porcine kidney diamine oxidase, PKDAO, and bovine plasma amine oxidase, BPAO, were saturated with the spin-trapping agent alpha-phenyl-N-t-butylnitrone, PBN, and incubated with cadaverine or benzylamine substrate, respectively, under aerobic conditions. EPR spectra due to trapped hydroxyl radicals were obtained for both enzymes with no evidence of superoxide formation. Under anaerobic conditions, hydroxyl radicals were formed only when H2O2 was present as well as substrate. Catalase prevented hydroxyl radical formation by PKDAO but not BPAO. The results indicate that hydroxyl radical is produced in the reaction of the product H2O2 with the reduced enzymes and therefore may be important in turnover-related enzyme degradation, but is not a true reaction intermediate. DA - 1993/// PY - 1993/// DO - 10.1016/0304-4165(93)90060-L VL - 1157 IS - 3 SP - 162-166 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0027270510&partnerID=MN8TOARS KW - SPIN TRAP KW - DIAMINE OXIDASE KW - PLASMA AMINE OXIDASE KW - HYDROXYL RADICAL KW - EPR ER - TY - JOUR TI - Simultaneous multi-site EPR spectroscopyin vivo AU - Smirnov, Alex I. AU - Norby, Shong-Wan AU - Clarkson, R. B. AU - Walczak, Ted AU - Swartz, Harold M. T2 - Magn. Reson. Med. AB - Abstract A gradient technique to measure electron paramagnetic resonance spectra simultaneously at several different locations is described. The technique is based on the use of point probes containing paramagnetic centers. The value of the magnetic field gradient is chosen to be sufficient to separate the EPR signals from the different paramagnetic probes yet at the same time small enough to change only minimally the shape of individual signals. The conditions to apply this technique are considered in detail. When experimental data have a high signal‐to‐noise ratio, the lineshape distortion induced by the gradient can be corrected with the aid of a known distribution function of paramagnetic centers within the probe. The maximum entropy deconvolution algorithm is successfully applied for the correction of significantly distorted lines. The technique is experimentally tested and applied to measure the concentration of oxygen in hypertrophied rat myocardium and normal rat kidney in vivo by low frequency EPR (L‐band, 1.2 GHz). No types of EPR oxygen‐sensitive probes‐lithium phthalocyanine crystals and synthetic carbohydrate chars‐were used. DA - 1993/8// PY - 1993/8// DO - 10.1002/mrm.1910300210 VL - 30 IS - 2 SP - 213-220 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0027312643&partnerID=MN8TOARS KW - ELECTRON PARAMAGNETIC RESONANCE KW - OXIMETRY KW - CARBONACEOUS MATERIALS KW - MYOCARDIUM ER - TY - JOUR TI - VOLTAMMETRIC CHARACTERIZATION OF SOLUBLE POLYACETYLENE DERIVATIVES OBTAINED FROM THE RING-OPENING METATHESIS POLYMERIZATION (ROMP) OF SUBSTITUTED CYCLOOCTATETRAENES AU - JOZEFIAK, TH AU - GINSBURG, EJ AU - GORMAN, CB AU - al., T2 - JOURNAL OF THE AMERICAN CHEMICAL SOCIETY DA - 1993/// PY - 1993/// VL - 115 IS - 11 SP - 4705-4713 ER - TY - JOUR TI - STRONGER ACCEPTORS CAN DIMINISH NONLINEAR OPTICAL-RESPONSE IN SIMPLE DONOR-ACCEPTOR POLYENES AU - MARDER, , SR AU - GORMAN, CB AU - TIEMANN, BG AU - al., T2 - JOURNAL OF THE AMERICAN CHEMICAL SOCIETY DA - 1993/// PY - 1993/// VL - 115 IS - 7 SP - 3006-3007 ER - TY - JOUR TI - SOLUBLE, HIGHLY CONJUGATED DERIVATIVES OF POLYACETYLENE FROM THE RING-OPENING METATHESIS POLYMERIZATION OF MONOSUBSTITUTED CYCLOOCTATETRAENES - SYNTHESIS AND THE RELATIONSHIP BETWEEN POLYMER STRUCTURE AND PHYSICAL-PROPERTIES AU - GORMAN, CB AU - GINSBURG, EJ AU - GRUBBS, RH T2 - JOURNAL OF THE AMERICAN CHEMICAL SOCIETY DA - 1993/// PY - 1993/// VL - 115 IS - 4 SP - 1397-1409 ER - TY - JOUR TI - RELATION BETWEEN BOND-LENGTH ALTERNATION AND 2ND ELECTRONIC HYPERPOLARIZABILITY OF CONJUGATED ORGANIC-MOLECULES AU - MARDER, , SR AU - PERRY, JW AU - BOURHILL, G AU - al., T2 - SCIENCE DA - 1993/// PY - 1993/// VL - 261 IS - 5118 SP - 186-189 ER - TY - JOUR TI - DIRECT OBSERVATION OF REDUCED BOND LENGTH ALTERNATION IN DONOR-ACCEPTOR POLYENES AU - MARDER, , SR AU - PERRY, JW AU - TIEMANN, BG AU - al., T2 - JOURNAL OF THE AMERICAN CHEMICAL SOCIETY DA - 1993/// PY - 1993/// VL - 115 IS - 6 SP - 2524-2526 ER - TY - JOUR TI - AN INVESTIGATION OF THE INTERRELATIONSHIPS BETWEEN LINEAR AND NONLINEAR POLARIZABILITIES AND BOND-LENGTH ALTERNATION IN CONJUGATED ORGANIC-MOLECULES AU - GORMAN, CB AU - MARDER, , SR T2 - PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA DA - 1993/// PY - 1993/// VL - 90 IS - 23 SP - 11297-11301 ER - TY - JOUR TI - Dramatic stabilization of ferricytochrome c upon reduction AU - Hilgen-Willis, Sharon AU - Pielak, Gary J. AU - Bowden, Edmond F. T2 - Journal of Inorganic Biochemistry AB - By combining measurements of the free energy of denaturation of the C102T variant of Saccharomyces cerevisiae iso-1-ferricytochrome c with determination of the formal potentials for the native and chemically-denatured states we have determined the free energy of denaturation of the ferro form of the protein. We report that the simplest of all chemical modifications, addition of an electron, increases the stability of ferricytochrome c by approximately 10 kcal mol−1 at 300 K, pH 4.6. This makes reduced cytochrome c one of the most stable proteins yet investigated. DA - 1993/8// PY - 1993/8// DO - 10.1016/0162-0134(93)85036-8 VL - 51 IS - 3 SP - 649-653 J2 - Journal of Inorganic Biochemistry LA - en OP - SN - 0162-0134 UR - http://dx.doi.org/10.1016/0162-0134(93)85036-8 DB - Crossref ER - TY - JOUR TI - Application of square wave voltammetry to strongly adsorbed quasireversible redox molecules AU - Reeves, James H. AU - Song, Shihua. AU - Bowden, Edmond F. T2 - Analytical Chemistry AB - ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTApplication of square wave voltammetry to strongly adsorbed quasireversible redox moleculesJames H. Reeves, Shihua. Song, and Edmond F. BowdenCite this: Anal. Chem. 1993, 65, 6, 683–688Publication Date (Print):March 1, 1993Publication History Published online1 May 2002Published inissue 1 March 1993https://doi.org/10.1021/ac00054a006RIGHTS & PERMISSIONSArticle Views655Altmetric-Citations72LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (689 KB) Get e-Alerts Get e-Alerts DA - 1993/3// PY - 1993/3// DO - 10.1021/ac00054a006 VL - 65 IS - 6 SP - 683-688 J2 - Anal. Chem. LA - en OP - SN - 0003-2700 1520-6882 UR - http://dx.doi.org/10.1021/ac00054a006 DB - Crossref ER - TY - JOUR TI - CONTINUOUS-FLOW FAST-ATOM-BOMBARDMENT LIQUID-CHROMATOGRAPHY MASS-SPECTROMETRY OF CAROTENOIDS AU - VANBREEMEN, RB AU - SCHMITZ, HH AU - SCHWARTZ, SJ T2 - ANALYTICAL CHEMISTRY AB - ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTContinuous-flow fast-atom-bombardment liquid chromatography/mass spectrometry of carotenoidsRichard B. Van Breemen, Harold H. Schmitz, and Steven J. SchwartzCite this: Anal. Chem. 1993, 65, 8, 965–969Publication Date (Print):April 15, 1993Publication History Published online1 May 2002Published inissue 15 April 1993https://doi.org/10.1021/ac00056a003RIGHTS & PERMISSIONSArticle Views181Altmetric-Citations39LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (524 KB) Get e-Alerts Get e-Alerts DA - 1993/4/15/ PY - 1993/4/15/ DO - 10.1021/ac00056a003 VL - 65 IS - 8 SP - 965-969 SN - 1520-6882 ER - TY - PAT TI - Optically pure D,E ring intermediates useful for the synthesis of camptothecin and camptothecin analogs AU - Comins, D. L. AU - Baesky, M. F. C2 - 1993/// DA - 1993/// PY - 1993/// ER - TY - PAT TI - Methods and intermediates for the assymmetric synthesis of camptothecin and camptothecin analogs AU - Comins, D. L. AU - Baesky, M. F. C2 - 1993/// DA - 1993/// PY - 1993/// ER - TY - PAT TI - Method of making intermediates useful for the manufacture of camptothecin and camptothecin analogs AU - Comins, D. L. AU - Baesky, M. F. C2 - 1993/// DA - 1993/// PY - 1993/// ER - TY - PAT TI - D ring intermediates for the synthesis of camptothecin and camptothecin analogs AU - Comins, D. L. AU - Baevsky, M. F. C2 - 1993/// DA - 1993/// PY - 1993/// ER - TY - PAT TI - Cycloalkyl-based chiral auxiliaries and method making the same AU - Comins, D. L. AU - Salvador, J. M. C2 - 1993/// DA - 1993/// PY - 1993/// ER - TY - PAT TI - Camptothecin intermediates and method of making same AU - Comins, D. L. AU - Baesky, M. F. C2 - 1993/// DA - 1993/// PY - 1993/// ER - TY - PAT TI - Camptothecin intermediate and method of making camptothecin intermediates AU - Comins, D. L. AU - Baesky, M. F. C2 - 1993/// DA - 1993/// PY - 1993/// ER - TY - PAT TI - Alkylpyridone DE ring intermediates useful for the manufacture of camptothecin and camptothecin analogs AU - Comins, D. L. AU - Baesky, M. F. C2 - 1993/// DA - 1993/// PY - 1993/// ER - TY - PAT TI - Alkoxymethylpyridine d-ring intermediates useful for the synthesis of camptpthecin and camptothecin analogs AU - Comins, D. L. AU - Baesky, M. F. C2 - 1993/// DA - 1993/// PY - 1993/// ER - TY - JOUR TI - CHARACTERIZATION OF CYTOCHROME-C ALKANETHIOLATE STRUCTURES PREPARED BY SELF-ASSEMBLY ON GOLD AU - SONG, S AU - CLARK, RA AU - BOWDEN, EF AU - TARLOV, MJ T2 - JOURNAL OF PHYSICAL CHEMISTRY AB - ADVERTISEMENT RETURN TO ISSUEPREVArticleCharacterization of cytochrome c/alkanethiolate structures prepared by self-assembly on goldShihua Song, Rose A. Clark, Edmond F. Bowden, and Michael J. TarlovCite this: J. Phys. Chem. 1993, 97, 24, 6564–6572Publication Date (Print):June 1, 1993Publication History Published online1 May 2002Published inissue 1 June 1993https://doi.org/10.1021/j100126a037RIGHTS & PERMISSIONSArticle Views1514Altmetric-Citations340LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (2 MB) Get e-Alerts DA - 1993/6/17/ PY - 1993/6/17/ DO - 10.1021/j100126a037 VL - 97 IS - 24 SP - 6564-6572 SN - 0022-3654 ER -