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Articles 1 - 30 of 30
Full-Text Articles in Chemistry
Pre-Methylation Of Lignin To Improve Storage Stability Of Oil Produced By Solvent Liquefaction, Jae-Young Kim, Parinaz Hafezi-Sefat, Sarah D. Cady, Ryan G. Smith, Robert C. Brown
Pre-Methylation Of Lignin To Improve Storage Stability Of Oil Produced By Solvent Liquefaction, Jae-Young Kim, Parinaz Hafezi-Sefat, Sarah D. Cady, Ryan G. Smith, Robert C. Brown
Sarah Cady
In this study, we methylated hydroxyl groups (phenolic hydroxyl: Phe-OH and aliphatic hydroxyl: Aliph-OH) in soda lignin (SL) prior to solvent liquefaction to improve storage stability of the resulting oil. We investigated two methylating reagents, dimethyl sulfate (DMS) and dimethyl carbonate (DMC), for selective Phe-OH and total hydroxyl group (Phe-OH and Aliph-OH) blocking. Samples of SL, DMS-SL, and DMC-SL were depolymerized into oils under supercritical ethanol (350 °C). Both methylated lignins produced higher amounts of oils and smaller amounts of char compared to untreated SL due to suppressed charring reactions. Oil produced from SL had relatively higher functional group contents …
Recent Approaches In Designing Bioadhesive Materials Inspired By Mussel Adhesive Protein, Pegah Kord Forooshani, Bruce P. Lee
Recent Approaches In Designing Bioadhesive Materials Inspired By Mussel Adhesive Protein, Pegah Kord Forooshani, Bruce P. Lee
Bruce Lee
Marine mussels secret protein-based adhesives, which enable them to anchor to various surfaces in a saline, intertidal zone. Mussel foot proteins (Mfps) contain a large abundance of a unique, catecholic amino acid, Dopa, in their protein sequences. Catechol offers robust and durable adhe-sion to various substrate surfaces and contributes to the curing of the adhesive plaques. In this article, we review the unique features and the key functionalities of Mfps, catechol chemistry, and strategies for preparing catechol-functionalized poly- mers. Specifically, we reviewed recent findings on the contributions of various features of Mfps on interfacial binding, which include coacervate formation, surface …
Improvement Of Mechanical Properties And Water Stability Of Vegetable Protein Based Plastics, Gowrishankar Srinivasan
Improvement Of Mechanical Properties And Water Stability Of Vegetable Protein Based Plastics, Gowrishankar Srinivasan
Gowrishankar Srinivasan
Bio-renewable bio-degradable plastics are a potential solution to the growing problems of pollution caused by petroleum plastics and dependency on foreign nations for petroleum resources. One possible feed stock for these materials are vegetable proteins, especially from soy bean and corn. These proteins have relatively high molecular weights and have the potential of being processed with standard polymer processing technologies. But some issues that need to be addressed are their water instability (soy protein) and inferior mechanical properties as compared to petroleum derived plastics. In this study, soy protein isolates (SPI) and zein protein was processed with various additives and …
Bioactive Surface Modification Of Metal Oxides Via Catechol-Bearing Modular Peptides: Multivalent-Binding, Surface Retention, And Peptide Bioactivity, Wen Tang, Gina Policastro, Geng Hua, Kai Guo, Chrys Wesdemiotis, Gary Doll, Matthew Becker
Bioactive Surface Modification Of Metal Oxides Via Catechol-Bearing Modular Peptides: Multivalent-Binding, Surface Retention, And Peptide Bioactivity, Wen Tang, Gina Policastro, Geng Hua, Kai Guo, Chrys Wesdemiotis, Gary Doll, Matthew Becker
Gary L. Doll
A series of multivalent dendrons containing a bioactive osteogenic growth peptide (OGP) domain and surface-binding catechol domains were obtained through solid phase synthesis, and their binding affinity to hydroxyapatite, TiO2, ZrO2, CeO2, Fe3O4 and gold was characterized using a quartz crystal microbalance with dissipation (QCM-d). Using the distinct difference in binding affinity of the bioconjugate to the metal oxides, TiO2-coated glass slides were selectively patterned with bioactive peptides. Cell culture studies demonstrated the bioavailability of the OGP and that OGP remained on the surface for at least 2 weeks under in vitro cell culture conditions. Bone sialoprotein (BSP) and osteocalcein …
Forensic Significance Of Teal Colored Cashmere And Black Acrylic Fibers, Nicole M. Martin
Forensic Significance Of Teal Colored Cashmere And Black Acrylic Fibers, Nicole M. Martin
Nicole M Martin
Forensic Significance of Teal Colored Cashmere and Black Acrylic Fibers Textile fibers are a valuable type of trace evidence within forensic cases. They have the ability to connect a perpetrator to a victim and or a crime scene. Some types of fibers are more prevalent than others. The purpose of this research was to conduct a target fiber study in order to determine the significance of the selected fibers in a forensic case. Two fibers were selected from two different garments, black acrylic fiber and a teal colored cashmere fiber. Unknown fibers were collected from three local clothing stores and …
Polythiophene Nanocomposites For Photodegradation Applications: Past, Present And Future, Mohammad Mansoob Khan Dr, M. O. Ansari, S. A. Ansari, M. H. Cho
Polythiophene Nanocomposites For Photodegradation Applications: Past, Present And Future, Mohammad Mansoob Khan Dr, M. O. Ansari, S. A. Ansari, M. H. Cho
Dr. Mohammad Mansoob Khan
Polythiophene (PTh) has been the subject of considerable interest because of its good environmental stability, unique redox electrical behavior, stability in doped and neutral states, ease of synthesis, and wide range of applications in many fields. Apart from its applications in the electrical or electronic field, PTh has shown promising applications in photocatalytic degradation. The fabrication of a catalyst, metal oxides with PTh, extends the absorption range of the modified composite system, thereby enhancing the photocatalytic activity under UV or visible light irradiation. Substituted PTh, such as alkyl substitution, modifies the electronic properties of the polymer, thereby enlarging the potential …
Improvement Of Mechanical Properties And Water Stability Of Vegetable Protein Based Plastics, Gowrishankar Srinivasan
Improvement Of Mechanical Properties And Water Stability Of Vegetable Protein Based Plastics, Gowrishankar Srinivasan
Gowrishankar Srinivasan
Bio-renewable bio-degradable plastics are a potential solution to the growing problems of pollution caused by petroleum plastics and dependency on foreign nations for petroleum resources. One possible feed stock for these materials are vegetable proteins, especially from soy bean and corn. These proteins have relatively high molecular weights and have the potential of being processed with standard polymer processing technologies. But some issues that need to be addressed are their water instability (soy protein) and inferior mechanical properties as compared to petroleum derived plastics. In this study, soy protein isolates (SPI) and zein protein was processed with various additives and …
Dc Electrical Conductivity Retention And Electrical Compensation Of Polyaniline By Tio2 At Higher Loading Percentages In Polyaniline@Tio2 Nanocomposites, Mohammad Mansoob Khan Dr, M. O. Ansari, S. A. Ansari, M. H. Cho
Dc Electrical Conductivity Retention And Electrical Compensation Of Polyaniline By Tio2 At Higher Loading Percentages In Polyaniline@Tio2 Nanocomposites, Mohammad Mansoob Khan Dr, M. O. Ansari, S. A. Ansari, M. H. Cho
Dr. Mohammad Mansoob Khan
Electrically conductive HCl-doped polyaniline Pani)@titanium dioxide (TiO2) nanocomposites were prepared by the in-situ oxidative polymerization of aniline in the presence of different amounts of TiO2 nanoparticles. The synthesized Pani@TiO2 nanocomposites were confirmed by transmission electron microscopy, X-ray diffraction, UV-visible spectroscopy, and thermogravimetric analysis. The stability of the Pani@TiO2 nanocomposites in terms of their electrical conductivity retention was examined under isothermal and cyclic aging conditions, and compared with that of pure Pani. The Pani@TiO2 nanocomposites showed higher thermal stability than pure Pani. The effect of competitive doping/de-doping by TiO2 was examined at different Pani to TiO2 weight ratios. TiO2 at a …
Synthesis And Polymerization Of (E,E)-[6.2]-(2,5)Furanophane-1,5-Diene, Neil D. Doppler, Jeffrey H. Glans
Synthesis And Polymerization Of (E,E)-[6.2]-(2,5)Furanophane-1,5-Diene, Neil D. Doppler, Jeffrey H. Glans
Jeffrey H. Glans
The goal of this research is to polymerize (E,E)-[6.2]-(2,5)furanophane to give a linear polymer. It will be synthesized by a 1,8-Hofmann Elimination using trimethyl-[(E)-3-(5-methyl-2-furyl)allyl] ammonium iodide. This diene will then be polymerized. The resulting polymeric [3.2] furanophane will then be oxidized to form a polymeric macrocycle tetra ketone. This compound will be tested for cation complexation.
Synthesis And Polymerization Of (E,E)-[6.2]-(2,5)Furanophane-1,5-Diene, Neil D. Doppler, Jeffrey H. Glans
Synthesis And Polymerization Of (E,E)-[6.2]-(2,5)Furanophane-1,5-Diene, Neil D. Doppler, Jeffrey H. Glans
Jeffrey H. Glans
The goal of this research is to polymerize (E,E)-[6.2]-(2,5)furanophane to give a linear polymer. It will be synthesized by a 1,8-Hofmann Elimination using trimethyl-[(E)-3-(5-methyl-2-furyl)allyl] ammonium iodide. This diene will then be polymerized. The resulting polymeric [3.2] furanophane will then be oxidized to form a polymeric macrocycle tetra ketone. This compound will be tested for cation complexation.
Enhanced Thermoelectric Behaviour And Visible Light Activity Of Ag@Tio2/Polyaniline Nanocomposite Synthesized By Biogenic-Chemical Route, M. O. Ansari, Mohammad Mansoob Khan Dr, S. A. Ansari, J. Lee, M. H. Cho
Enhanced Thermoelectric Behaviour And Visible Light Activity Of Ag@Tio2/Polyaniline Nanocomposite Synthesized By Biogenic-Chemical Route, M. O. Ansari, Mohammad Mansoob Khan Dr, S. A. Ansari, J. Lee, M. H. Cho
Dr. Mohammad Mansoob Khan
This paper reports the synthesis of visible light-active Ag@TiO2/Pani nanocomposite through a facile biogenic-chemical route. Ag@TiO2/Pani nanocomposite was prepared by the in-situ oxidative polymerization of aniline in the presence of Ag@TiO2 nanocomposite, which was obtained via a biogenic route. The synthesized Ag@TiO2/Pani nanocomposite was confirmed by UV-visible spectroscopy, photoluminescence spectroscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and thermogravimetric analysis. The Ag@TiO2/Pani nanocomposite was doped with HCl or para-toluene sulfonic acid to render it conducting. An analysis of the thermoelectrical behavior using a cyclic aging technique showed that the electrical conductivity and thermal stability of Pani got improved after …
Enhanced Thermal Stability Under Dc Electrical Conductivity Retention And Visible Light Activity Of Ag/Tio2@Polyaniline Nanocomposite Film, M. O. Ansari, Mohammad Mansoob Khan Dr, S. A. Ansari, K Raju, J Lee, M. H. Cho
Enhanced Thermal Stability Under Dc Electrical Conductivity Retention And Visible Light Activity Of Ag/Tio2@Polyaniline Nanocomposite Film, M. O. Ansari, Mohammad Mansoob Khan Dr, S. A. Ansari, K Raju, J Lee, M. H. Cho
Dr. Mohammad Mansoob Khan
The development of organic-inorganic photoactive materials has resulted in significant advancements in heterogeneous visible light photocatalysis. This paper reports the synthesis of visible light-active Ag/TiO2@Pani nanocomposite film via a simple biogenic-chemical route. Electrically conducting Ag/TiO2@Pani nanocomposites were prepared by incorporating Ag/TiO2 in N-methyl-2-pyrrolidone solution of polyaniline (Pani), followed by the preparation of Ag/TiO2@Pani nanocomposite film using solution casting technique. The synthesized Ag/TiO2@Pani nanocomposite was confirmed by UV-visible spectroscopy, photoluminescence spectroscopy, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and thermogravimetric analysis. The Ag/TiO2@Pani nanocomposite film showed superior activity towards the photodegradation of methylene blue under visible light compared to Pani, …
Polymer Gel Templating Of Free-Standing Inorganic Monoliths For Photocatalysis, Xiaojuan Fan, Honghan Fei, David Demaree, Daniel Brennan, Jessica St. John, Scott Oliver
Polymer Gel Templating Of Free-Standing Inorganic Monoliths For Photocatalysis, Xiaojuan Fan, Honghan Fei, David Demaree, Daniel Brennan, Jessica St. John, Scott Oliver
Xiaojuan Fan
We have developed a simple, low-cost process to fabricate free-standing porous metal oxide monoliths. Various swollen polymers and hydrogels possessing an open network structure are infiltrated with pure liquid metal alkoxide. Hydrolysis followed by chemical or thermal degradation of the polymer leads to bulk porous monoliths, TiO2 and SiO2 as initial examples. The titania solids were subsequently employed as photocatalysts under UV light and monitored for adsorption. The materials show efficient reusable photocatalytic ability as compared to pure-phase nanoparticle titanium oxide.
Introduction To Molecular Motion In Polymers (Book Review), Jeffrey H. Glans
Introduction To Molecular Motion In Polymers (Book Review), Jeffrey H. Glans
Jeffrey H. Glans
A book review by Jeffrey H. Glans. Pethrick, Richard A., T. Amornsakchai, and A. M. North. Introduction to Molecular Motion in Polymers. Dunbeath, Scotland: Whittles Pub.; Boca Raton, FL: Distributed in North America by CRC, 2011. ISBN 9781849950084
Fluorescent Ratiometric Indicators Based On Cu(Ii)-Induced Changes In Poly(Nipam) Microparticle Volume, Shawn Burdette, John Osambo, W.Rudolf Seitz, Daniel Kennedy, Roy Planalp, Aaron Jones, Randy Jackson
Fluorescent Ratiometric Indicators Based On Cu(Ii)-Induced Changes In Poly(Nipam) Microparticle Volume, Shawn Burdette, John Osambo, W.Rudolf Seitz, Daniel Kennedy, Roy Planalp, Aaron Jones, Randy Jackson
Shawn C. Burdette
Microparticles consisting of the thermal responsive polymer N-isopropyl acrylamide (polyNIPAM), a metal ion-binding ligand and a fluorophore pair that undergoes fluorescence resonance energy transfer (FRET) have been prepared and characterized. Upon the addition of Cu(II), the microparticles swell or contract depending on whether charge is introduced or neutralized on the polymer backbone. The variation in microparticle morphology is translated into changes in emission of each fluorophore in the FRET pair. By measuring the emission intensity ratio between the FRET pair upon Cu(II) addition, the concentration of metal ion in solution can be quantified. This ratiometric fluorescent indicator is the newest …
Synthesis And Characterization Of Cuo Nanosheets In Polyvinylpyrrolidone By Quick Precipitation Method, Mahdi Shahmiri
Synthesis And Characterization Of Cuo Nanosheets In Polyvinylpyrrolidone By Quick Precipitation Method, Mahdi Shahmiri
mahdi shahmiri
In this project, CuO nanosheets were grown successfully in polyvinylpyrrolidone (PVP) by a simple and quick chemical method in the absence of templates. Copper nitrate, PVP and sodium hydroxide were used as copper precursor, stabilizer and accelerator, respectively. The products were characterized by X-ray diffraction (XRD), UV–vis spectroscopy, field emission scanning electron microscopy (FE-SEM), energy dispersive analysis of X-rays (EDAX), transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) spectroscopy. The result of the XRD and EDAX confirmed the formation of pure single-phase CuO. Generation of the CuO nanosheets and nanorods were confirmed by UV–visible spectra. FE-SEM depicted that layered …
Hyaluronic Acid Based Self-Assembling Nanosystems For Cd44 Target Mediated Sirna Delivery To Solid Tumors., Arun Iyer
Arun Iyer
Anticancer therapeutics employing RNA interference mechanism holds promising potentials for sequence-specific silencing of target genes. However targeted delivery of siRNAs to tumor tissues and cells and more importantly, their intracellular release at sites of interest still remains a major challenge that needs to be addressed before this technique could become a clinically viable option. In the current study, we have engineered and screened a series of CD44 targeting hyaluronic acid (HA) based self-assembling nanosystems for targeted siRNA delivery. The HA polymer was functionalized with lipids of varying carbon chain lengths/nitrogen content, as well as polyamines for assessing siRNA encapsulation. From …
Solid State Chemical Reactions And Polymerizations: The Initial Synthesis Of Dna?, Otto Vogl, Frank T. Traceski
Solid State Chemical Reactions And Polymerizations: The Initial Synthesis Of Dna?, Otto Vogl, Frank T. Traceski
Otto Vogl
A Proposal for Covering individual Macromolecules with Macromolecules including a Realistic Chiral Synthesis of Nucleic Acids.
Synthesis And Characterization Of Linear And Branched Polylactic Acid For Use In Food Packaging Applications, Kyle C. Bentz
Synthesis And Characterization Of Linear And Branched Polylactic Acid For Use In Food Packaging Applications, Kyle C. Bentz
Kyle C Bentz
Polylactic acid (PLA) resins of various molecular weights and molecular weight distributions were synthesized. Linear, narrow molecular weight distribution (MWD) PLA resins were synthesized, as well as resins containing both high molecular weight branched structures and low molecular weight chains and oligomers. Narrow MWD resins were synthesized for use as adhesives for corrugated paperboard and broad MWD resins were synthesized for use as a waterborne coating. PLA resins were dispersed for use as a waterborne coating. Success has been made at forming films utilizing various plasticizers and surfactants as well as polyvinyl alcohol as dispersing agents. A cold dispersion procedure …
Synthesis, Characterization And Nonlinear Optical Properties Of Silver/Pva Nanocomposites, Mahdi Shahmiri
Synthesis, Characterization And Nonlinear Optical Properties Of Silver/Pva Nanocomposites, Mahdi Shahmiri
mahdi shahmiri
Silver/polyvinyl alcohol (PVA) nanocomposites are prepared via quick precipitation method, using hydrazine as a reducing agent. Preparing of silver/PVA nanocomposites by this method is done for the first time. The samples are characterized by Uv-Visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM). Nonlinear optical properties are carried out by Z-scan technique using a blue CW laser beam operated at wavelength 405 nm. It is shown that the synthesized samples have negative nonlinear refractive index and the magnitude is in the order of 108. The nonlinear refractive index increases as amount of reducing agent increases.
Nanoscale Toughness And Behavior Of Graphene/Epoxy Interfaces, Nima Rahbar, Hossein Salahshoor
Nanoscale Toughness And Behavior Of Graphene/Epoxy Interfaces, Nima Rahbar, Hossein Salahshoor
Nima Rahbar
Atomistic simulations are performed to investigate the nano-scale interfacial fracture toughness between graphene and epoxy. Nano-mechanical properties of graphene and epoxy are initially studied using molecular dynamics simulations. A novel method is suggested to accurately model the behavior of the graphen/epoxy interface during the curing process of the epoxy as a function of temperature. The computed interfacial fracture energy is computed at about 0.203 J/m2, which is in good agreement with available experimental data. It is also shown that the adhesion between cured epoxy and graphene layer increases the pre-existing waviness of the 2-dimensional graphene sheet in a 3-dimensional space. …
Surface Investigation Of Chitosan Film With Fatty Acid Monolayers, M Misran
Surface Investigation Of Chitosan Film With Fatty Acid Monolayers, M Misran
Misni Misran
The surface pressure-molecular area (pi-A) isotherm curves of two fatty acids of different chain lengths, i.e. stearic (C(18)) and arachidic (C(20)) acids, were obtained by using Langmuir-Blodgett (LB) technique. Results showed clear isotherm plots with limiting mean molecular area around 21 angstrom(2) for both acids. However, the monolayer was found to collapse at higher than 33 mN m(-1) and 21 mN m(-1) for stearic acid and arachidic acid respectively. The effect of Langmuir-Blodgett monolayers of the acids was investigated by atomic force microscopy (AFM). Chitosan film, before and after dipping in water, was also studied by means of AFM so …
Meine Jugend In Traiskirchen, Otto Vogl
Tuning Nonlinear Optical Properties In Π-Delocalizable Ruthenium Complexes, T. Christopher Corkery, Sanjay S. Chavan, Marie P. Cifuentes, Marek Samoc, Stijn Van Cleuvenbergen, Inge Asselberghs, Koen Clays, Mark G. Humphrey
Tuning Nonlinear Optical Properties In Π-Delocalizable Ruthenium Complexes, T. Christopher Corkery, Sanjay S. Chavan, Marie P. Cifuentes, Marek Samoc, Stijn Van Cleuvenbergen, Inge Asselberghs, Koen Clays, Mark G. Humphrey
Chris Corkery
No abstract provided.
Octa-N-Butyl-1kappac,2kappac,3kappac,4kappac-Tetra-Kis(Mu-2-Hydroxy-Benzoato)-1:2 Kappao:O;2:3kappao:O';3:4kappao:O;1:4kappao:O'-Di-Mu(3)-Oxido-1:2:3kappao:O:O;1:3 :4kappao:O:O-Tetra-Tin(Iv), M Misran
Misni Misran
In the centrosymmetric tetra-nuclear title compound, [Sn4(C4H9)8(C7H5O3) 4O2], one of the two independent Sn atoms is five-coordinate in a cis-C2SnO3 trigonal-bipyramidal geometry [C - Sn - C = 142.7 (1)°]; the geometry is distorted owing to a long Sn⋯O(double bond) inter-action [Sn⋯O = 2.862 (1) Å]. The other Sn atom has a bent R 2Sn skeleton [C - Sn - C = 144.0 (1)°], but the geometry is best regarded as being a trans-C2SnO4 octa-hedron as the Sn-O(single bond) inter-action is shorter [Sn - O = 2.674 (1) Å].
Tuning Nonlinear Optical Properties, T. Christopher Corkery, Marie P. Cifuentes, Marek Samok, Mark G. Humphrey
Tuning Nonlinear Optical Properties, T. Christopher Corkery, Marie P. Cifuentes, Marek Samok, Mark G. Humphrey
Chris Corkery
No abstract provided.
Nature Of The Si-N Bond In Silatranes, Mark S. Gordon, Marshall T. Carroll, Jan H. Jensen, Larry P. Davis, Larry W. Burggraf, R. Martin Guidry
Nature Of The Si-N Bond In Silatranes, Mark S. Gordon, Marshall T. Carroll, Jan H. Jensen, Larry P. Davis, Larry W. Burggraf, R. Martin Guidry
Mark S. Gordon
Both ab initio and semiempirical calculations are used to investigate the structure and bonding in substituted silatranes. In agreement with gas-phase experiments, which fmd Si-N distances that are 0.25-0.35 A longer than those in the crystal phase, the Si-N distance (for example, in methylsilatrane) is predicted to be much larger than that observed in the crystal. Nonetheless, a bond critical point is found between Si and N, suggesting the existence of an Si-N bond in these compounds. It is found that the energy cost for constraining the Si-N distance in hydroxysilatrane to a value similar to that observed in the …
A New Twist On Pseudorotation, Theresa L. Windus, Mark S. Gordon, Larry W. Burggraf, Larry P. Davis
A New Twist On Pseudorotation, Theresa L. Windus, Mark S. Gordon, Larry W. Burggraf, Larry P. Davis
Mark S. Gordon
For pentacoordinated structures in a trigonal bipyramidal ar· rangement, Berry1 proposed a "pseudorotation" mechanism whereby two such isomers can interconvert through a tetragonal transition state (TS). This Berry pseudorotation mechanism was demonstrated explicitly for SiH5- by following the MP22/6· 31G(d)3 minimum energy path4 (MEP).
Gas-Phase And Computational Studies Of Pentacoordinate Silicon, Robert Damrauer, Larry W. Burggraf, Larry P. Davis, Mark S. Gordon
Gas-Phase And Computational Studies Of Pentacoordinate Silicon, Robert Damrauer, Larry W. Burggraf, Larry P. Davis, Mark S. Gordon
Mark S. Gordon
We have demonstrated that a wide variety of pentacoordinate silicon anions (siliconates) should be stable and can be prepared by combining the predictive powers of MNDO and ab initio computational methods and the flowing afterglow (FA) experimental technique. MNDO has been used to compute the anion affinities of 91 siliconates; all but five of these are predicted to be stable with respect to the loss of an anion. Twenty-four siliconates, most of them previously unreported, have been prepared and studied in the FA. The MNDO predictions were, in general, consistent with the experimental results and with trends previously reported by …
Thermal Decomposition Of Silane, Mark S. Gordon, David R. Gano, J. Stephen Binkley, Michael J. Frisch
Thermal Decomposition Of Silane, Mark S. Gordon, David R. Gano, J. Stephen Binkley, Michael J. Frisch
Mark S. Gordon
The essential features of the potential energy surface for the thermal decomposition of silane have been calculated with extended basis sets, augmented by correlation corrections. It is predicted that the transition state for the molecular elimination lies 56.9 kcaljmol above silane. For the reverse reaction, the transition state is less than 2 kcal/mol above the separated fragments, silylene and molecular hydrogen, but 4.8 kcal/mol above a long-range potential well. In the latter, the silylene-H2 separation is 1.78 A, and the bond in H2 has stretched by more than 0.05 A. This indicates a significant electronic interaction between the fragments even …