| Preparation and Characterization of the Binary Group 13 Azides M(N3)3 and M(N3)3'CH3CN (M = Ga, In, TI), [Ga(N3)5](2-), and [M(N3)6](3-) (M = In, TI) (Preprint) |
24 MAY 2011 |
90 pages |
| Authors:
Ralf Haiges; Jerry A. Boatz; Jodi M. Williams; Karl O. Christe; UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES
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 | There has been much interest in polyazido compounds during the last two decades. In particular, the potential of group 13 azides as precursors for the synthesis of the corresponding nitrides has been studied in great detail due to their usefulness for semiconductor and optoelectronic applications. Although most of these efforts were devoted to gallium azides, aluminium and indium azides were also explored. For thallium, the monoazide is well known and ... |
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| Design of Energetic Ionic Liquids |
27 APR 2011 |
10 pages |
| Authors:
Jerry A. Boatz; Gregory A. Voth; Mark S. Gordon; Sharon Hammes-Schiffer; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| An essential need of the US Air Force is the discovery, development, and fielding of new, energetic materials for advanced chemical propulsion in space and missile applications. Some of the key factors driving the requirement for new chemical propellants include: (a) improved performance in terms of increased specific impulse and density, (b) reduced sensitivity to external stimuli such as impact, friction, shock, and electrostatic discharge, and (c) mitigation of environmental ... |
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| Why are [P(C6H5)4]+N3- and [As(C6H5)4]+N3- Ionic Salts and Sb(C6H5)4N3 and Bi(C6H5)4N3 are Covalent Solids? A Theoretical Study Provides an Unexpected Answer |
04 MAR 2011 |
75 pages |
| Authors:
Karl O. Christe; Ralf Haiges; Jerry A. Boatz; H. D. Jenkins; Edward B. Garner; David A. Dixon; UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES LOKER HYDROCARBON RESEARCH INST
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| A recent crystallographic study has shown that, in the solid state, P(C6H5)4N3 and As(C6H5)4N3 have ionic [M(C6H5)4]+N3- type structures, whereas Sb(C6H5)4N3 exists as a pentacoordinated covalent solid. Using the results from density functional theory, lattice energy (VBT) calculations, sublimation energy estimates, and Born-Fajans-Haber cycles, it is shown that the maximum coordination numbers of the central atom M, the lattice energies of the ionic solids, and the sublimation energies of the ... |
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| Design of Energetic Ionic Liquids (Preprint) |
27 AUG 2007 |
8 pages |
| Authors:
Jerry A. Boatz; Hui Li; Mark S. Gordon; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| An essential need of the US Air Force is the discovery, development, and fielding of new, energetic materials for advanced chemical propulsion in space and missile applications. Some of the key factors driving the requirement for new chemical propellants include: (a) improved performance in terms of increased specific impulse and density, (b) reduced sensitivity to external stimuli such as impact, friction, shock, and electrostatic discharge, and (c) mitigation of environmental ... |
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| Cation-Cation pi-pi Stacking in Small Ionic Clusters of 1,2,4-Triazolium (Preprint) |
12 JUL 2007 |
4 pages |
| Authors:
Hui Li; Jerry A. Boatz; Mark S. Gordon; NEBRASKA UNIV LINCOLN DEPT OF CHEMISTRY
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| Aromatic cations such as imidazolium and its derivatives have delocalized charges and, therefore, are often used to synthesize functional nanomaterials, low-melting salts and ionic liquids. Recently, energetic low-melting salts and ionic liquids based on triazolium and its derivatives have received considerable attention. A characteristic property of aromatic compounds is their ability to form pi-pi stacking structures, which can have significant influence on properties. Cation-cation pi-pi stacking structures are less common, ... |
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| Polynitrogen/Nanoaluminum Surface Interactions (Challenge Project C2V) (Preprint) |
08 MAY 2007 |
8 pages |
| Authors:
Jerry A. Boatz; Dan C. Sorescu; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| First-principles density functional theory (DFT) calculations using the generalized gradient approximation (GGA) have been conducted to study the adsorption of a series of high-nitrogen compounds of increasing sizes and complexity on the Al(111) surface. The calculations employ periodic slab models with 4 Al layers, ranging in size from (3x3) to (7x7) surface unit cells, and containing up to 196 Al atoms. Complementary quantum chemical calculations, utilizing DFT and second-order perturbation ... |
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| Design of Energetic Ionic Liquids (Challenge Project C2H) (Preprint) |
04 MAY 2007 |
9 pages |
| Authors:
Jerry A. Boatz; Mark S. Gordon; Greg A. Voth; Sharon Hammes-Schiffer; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| The focus of this challenge project is on theoretical studies of ionic liquids as advanced monopropellants for rocket, missile, and satellite propulsion applications. Ionic liquids offer several advantages over conventional monopropellants such as hydrazine, including higher energy content, higher densities, very low vapor pressures, and reduced vapor toxicities. They are likewise well suited for use as working fluids in electric propulsion devices. The properties of ionic liquids may be tuned ... |
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| Synthesis and Characterization of Silyldichloramines, Their Reactions with F Ions, Stability of N2Cl(2) and NCl(2), and Formation of NCl(3) (PREPRINT) |
2007 |
33 pages |
| Authors:
Stefan Schneider; Michael Gerken; Ralf Haiges; Thorsten Schroer; Jerry A. Boatz; Karl O. Christe; ENGINEERING RESEARCH AND CONSULTING INC (ERC INC) EDWARDS AFB CA
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| Only two silyldichloramines, (C6H5)3SiNCl(2) and (CH3)3SiNCl(2), have been reported in the literature. The synthesis of the former was successfully repeated, and its structure was established by single crystal X-ray diffraction and vibrational spectroscopy. Attempts to prepare (CH3)3SiNCl(2) were unsuccessful, however, a new trialkylsilyldichloramine, t-BuMe2Si-NCl(2), was prepared and characterized by Raman and multinuclear NMR spectroscopy. The reaction of t-BuMe2SiNCl(2) with (CH3)4NF in CHF3 solution at -78 deg. C, followed by removal ... |
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| Polyazido Pyrimidines: High Energy Compounds and Precursors to Carbon Nanotubes (PREPRINT) |
13 JUL 2006 |
18 pages |
| Authors:
Chengfeng Ye; Haoxiang Gao; Brendan Twamley; Jean'ne M. Shreeve; Gregory W. Drake; Jerry A. Boatz; IDAHO UNIV MOSCOW DEPT OF CHEMISTRY
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| Organic polyazido substituted compounds are at the forefront of high energy research. Polyazido organic compounds have high relative heats of formation as one azido group adds about 87 kcal/mol of endothermicity to a hydrocarbon compound. In this family of compounds, 3,6-di(azido)-tetrazine (1), has the highest reported heat of formation ~ 1101 kJ mol-1(6709 kJ kg-1). The compound 4,4',6,6'-tetra(azido)azo-1,3,5-triazine (2), has a heat of formation of 2171 (6164 kJ kg -1). ... |
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| Correlation of Calculated Halonium Ion Structures with Experimental Product Distributions from Terminal Alkenes: The Effect of Electron-Withdrawing Fluorine Substituents on the Structure and Charge Localization of Halonium Ions (PREPRINT) |
03 APR 2006 |
24 pages |
| Authors:
Dale F. Shellhamer; David C. Gleason; Sean J. Rodriguez; Victor L. Heasley; Jerry A. Boatz; Jeffrey J. Lehman; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| The structures and charge densities of halonium ions, derived from addition of halogen electrophiles to fluoro-substituted terminal alkenes, were computed using quantum chemical methods. Geometry optimizations were performed at the second-order perturbation theory level (MP2, also known as MBPT(2)), using the Spartan02 program and also at the density functional theory level, using the GAMESS quantum chemistry code with the B3LYP hybrid functional. An additional set of B3LYP calculations incorporating the ... |
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| Experimental Evidence for Linear Metal-Azide Bonds. The Binary Group 5 Azides Nb(N3)5, Ta(N3)5, [Nb(N3)6]- and [Ta(N3)6]-, and 1:1 Adducts of Nb(N3)5 and Ta(N3)5 with CH3CN (PREPRINT) |
20 MAR 2006 |
37 pages |
| Authors:
Ralf Haiges; Jerry A. Boatz; Thorsten Schroer; Muhammed Yousufuddin; Karl O. Christe; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| Whereas the existence of numerous binary transition metal azido-complexes has been reported, no binary Group 5 azides are known. Only a limited number of partially azide-substituted compounds of vanadium, niobium and tantalum have previously been reported. In this paper, we wish to communicate the synthesis and characterization of Nb(N3)5, Ta(N3)5 and their 1:1 adducts with CH3CN, and of the anions [Nb(N3)6]- and [Ta(N3)6]-. The crystal structures of Nb(N3)5-CH3CN and [PPh4][Nb(N3)6] ... |
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| Experimental Evidence for Linear Metal-Azide Coordination: The Binary Group 5 Azides [Nb(N3)5], [Ta(N3)5], [Nb(N3)6], and [Ta(N3)6], and 1:1 Acetonitrile Adducts [Nb(N3)5(CH3CN)] and (Ta(N3)5(CH3CN)) |
20 MAR 2006 |
7 pages |
| Authors:
Ralf Haiges; Thorsten Schroer; Muhammed Yousufuddin; Karl Christe; Jerry A. Boatz; UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES LOKER HYDROCARBON RESEARCH INST
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| Whereas the existence of numerous binary transition metal azido-complexes has been reported, no binary Group 5 azides are known. Only a limited number of partially azide-substituted compounds of vanadium, niobium and tantalum have previously been reported. In this paper, we wish to communicate the synthesis and characterization of Nb(N3)5, Ta(N3)5 and their 1:1 adducts with CH3CN, and of the anions [Nb(N3)6]- and [Ta(N3)6]-. The crystal structures of [Nb(N3)5(CH3CN)] and [PPh4][Nb(N3)6] ... |
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| Polyazide Chemistry: Synthesis and Properties of [Nb(N3)7]2- and [Ta(N3)7]2- (PREPRINT) |
16 MAR 2006 |
39 pages |
| Authors:
Ralf Haiges; Jerry A. Boatz; Muhammed Yousufuddin; Karl O. Christe; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| During the last decade, inorganic polyazido compounds have received much attention. Besides being of academic interest, azides and polyazides are viable candidates for high energy-density materials (HEDM). The azido group is very energetic and polyazides are highly endothermic compounds, whose energy content increases with an increasing number of azido ligands. It is, therefore, not surprising that the synthesis of molecules with a high number of azido groups is very challenging ... |
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| Preparation, Characterization, and Crystal Structures of the SO(3)NHF- and SO(3)NF(2)-Anions (PREPRINT) |
16 MAR 2006 |
29 pages |
| Authors:
Ralf Haiges; Ross Wagner; Jerry A. Boatz; Muhammed Yousufuddin; Markus Etzkorn; G. K. Prakash; Karl O. Christe; Robert D. Chapman; Mark F. Welker; Charles B. Kreutzberger; UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES LOKER HYDROCARBON RESEARCH INST
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| Recently, a new class of high-energy-containing materials, gem-bis(difluoramino)-substituted heterocyclic nitramines, has gained attention as high-energy oxidizers: HNFX and TNFX have been successfully synthesized under strongly acidic conditions from their corresponding ketone derivatives using an excess of difluoramine. HNF2 is an unpredictably shock-sensitive and thermally unstable, gaseous compound which can be generated from different precursors, e.g., tetrafluorohydrazine, N,N-difluorourea, N,N-difluorocarbamates, or trityldifluoramine. Out of these precursors, only trityldifluoramine is a stable storable ... |
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| Electronic Structure Studies of High Energy Ionic Liquids (PREPRINT) |
18 JAN 2006 |
37 pages |
| Authors:
Deborah D. Zorn; Mark S. Gordon; Jerry A. Boatz; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| New energetic ionic liquids are investigated as potential high energy density materials. Ionic liquids are composed of large, charge-diffuse cations, coupled with various (usually oxygen containing) anions. In this work, calculations have been performed on thetetrazolium cation with a variety of substituents. Density functional theory (DFT) with the B3LYP functional, using the 6-311G(d,p) basis set was used to optimize geometries. Improved treatment of dynamic electron correlation was obtained using second ... |
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| Electronic Structure Studies of Tetrazolium-Based Ionic Liquids |
2006 |
11 pages |
| Authors:
Deborah D. Zorn; Mark S. Gordon; Jerry A. Boatz; AIR FORCE RESEARCH LAB EDWARDS AFB CA SPACE AND MISSILE PROPULSION DIV
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| New energetic ionic liquids are investigated as potential high energy density materials. Ionic liquids are composed of large, charge-diffuse cations, coupled with various (usually oxygen containing) anions. In this work, calculations have been performed on the tetrazolium cation with a variety of substituents. Density functional theory (DFT) with the B3LYP functional, using the 6-311G(d,p) basis set was used to optimize geometries. Improved treatment of dynamic electron correlation was obtained using ... |
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| The Moment Analysis Method as Applied to the (2)S yields (2)P Transition in Cryogenic Alkali Metal/Rare Gas Matrices |
14 DEC 2005 |
10 pages |
| Authors:
Heidi A. Vosbein; Jerry A. Boatz; III Kenney John W.; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| The moment analysis method (MA) has been tested for the case of (2)S yields (2)P transitions of alkali metal atoms (M) doped into cryogenic rare gas (Rg) matrices using theoretically validated simulations. Theoretical/computational M/Rg system models are constructed with precisely defined parameters that closely mimic known M/Rg systems. Monte Carlo (MC) techniques are then employed to generate simulated absorption and magnetic circular dichroism (MCD) spectra of the (2)S yields (2)P ... |
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| The Moment Analysis Method as Applied to the 2S-2P Transition in Cryogenic Alkali Metal/Rare Gas Matrices (PREPRINT) |
05 DEC 2005 |
35 pages |
| Authors:
Heidi A. Terrill Vosbein; Jerry A. Boatz; John W. Kenney; AIR FORCE RESEARCH LAB EDWARDS AFB CA SPACE AND MISSILE PROPULSION DIV
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| The moment analysis method (MA) has been tested for the case of 2 S→2P ([core]ns1→[core]np1) transitions of alkali metal atoms (M) doped into cryogenic rare gas (Rg) matrices using theoretically validated simulations. Theoretical/computational M/Rg system models are constructed with precisely defined parameters that closely mimic known M/Rg systems. Monte Carlo (MC) techniques are then employed to generate simulated absorption and magnetic circular dichroism (MCD) spectra of the 2 S→2P M/Rg ... |
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| Experimental Evidence for Linear Metal-Azide Bonds. The Binary Group 5 Azides Nb(N3)5, Ta(N3)5, [Nb(N3)6]- and [Ta(N3)6]-, and 1:1 Adducts of Nb(N3)5 and Ta(N3)5 with CH3CN |
27 APR 2005 |
39 pages |
| Authors:
Ralf Haiges; Jerry A. Boatz; Thorsten Schroer; Muhammed Yousufuddin; Karl O. Christe; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| Whereas numerous binary transition metal azido-complexes have been reported, no binary Group 5 azides are known. Only a limited number of partially azide-substituted compounds of vanadium, niobium and tantalum have previously been reported. In this paper, we wish to communicate the synthesis and characterization of Nb(N3)5, Ta(N3)5 and their 1:1 adducts with CH3CN, and of the anions [Nb(N3)6]- and [Ta(N3)6]-. We also report the crystal structures of Nb(N3)5 CH3CN and ... |
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| Structural Isomers of bis(pentazolyl)iron(II): A Theoretical Study |
22 APR 2005 |
27 pages |
| Authors:
Jerry A. Boatz; Karl Christe; Ashwani Vij; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| The High Energy Density Materials (HEDM) Program objectives are: Identifying and developing advanced chemical propellants for rocket propulsion applications; specific impulse (Isp) is the major metric of a propellant's performance; density can also be a significant contributor. |
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| Theory of Monte-Carlo Simulations of the Magnetic Circular Dichroism (MCD) Spectra of Alkali Metal/Rare Gas Systems (POSTPRINT) |
09 MAR 2005 |
13 pages |
| Authors:
John W. Kenney; Jerry A. Boatz; Heidi A. Vosbein; CONCORDIA UNIV IRVINE CA
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| The history of magnetic circular dichroism (MCD) spectroscopy in the study of alkali metal/rare gas (M/Rg) cryogenic systems is reviewed in the context of developing a better understanding of alkali metal/hydrogen systems of current interest to the U.S. Air Force as enhanced-performance cryogenic rocket propellants. A new theory for simulating the MCD spectra of M/Rg systems is presented together with a careful discussion of the theory's implicit and explicit approximations ... |
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