The Hamiltonian for triatomic and tetraatomic systems in row-orthonormal hyperspherical coordinates has been derived previously. However, for pentaatomic systems this derivation requires nontrivial...
Chu, Tian-Shu, Han, Ke-Li, Hankel, Marlies, Balint-Kurti, Gabriel G., Kuppermann, Aron, Abrol, Ravinder
Real wave packet propagations were carried out on both a single ground electronic state and two-coupled-electronic states of the title reaction to investigate the extent of nonadiabatic effects on...
Geometric phase effects in H3 predissociation (2007)
Lepetit, Bruno, Abrol, Ravinder, Kuppermann, Aron
We model the predissociation of H3 in the electronic state corresponding to the upper sheet of the conically intersecting 1 2A[prime] and 2 2A[prime] states, and we show that product-state...
Numerical generation of hyperspherical harmonics for tetra-atomic systems (2006)
Lepetit, Bruno, Wang, Desheng, Kuppermann, Aron
A numerical generation method of hyperspherical harmonics for tetra-atomic systems, in terms of row-orthonormal hyperspherical coordinates—a hyper-radius and eight angles—is presented. The...
Wilson, Leroy E., Benson, Sidney, Cool, Terry, Javan, Ali, Kuppermann, Aron
This report summarizes the ideas generated by a committee of consultants. The purpose of the meeting was to recommend an approach for finding new efficient gas lasers where the inversion is obtained...
Abrol, Ravinder, Kuppermann, Aron
Molecular reaction dynamics in the adiabatic representation is complicated by the existence of conical intersections and the associated geometric phase effect. The first-derivative coupling vector...
Schatz,George C., Kuppermann,Aron
Accurate quantum mechanical transition probabilities and rate constants for vibrational deactivation via reactive and nonreactive collisions in collinear H + FH(v), D + FD(v), H + FD(v), and D +...
Hyperspherical harmonics for tetraatomic systems (2001)
Wang, Desheng, Kuppermann, Aron
A recursion procedure for the analytical generation of hyperspherical harmonics for tetraatomic systems, in terms of row-orthonormal hyperspherical coordinates, is presented. Using this approach and...
The state-to-state asymptotic analysis of tetraatomic reactions is presented. It is assumed that the four-atom time-independent partial wave Schrödinger equation has been solved subject to the...
Accurate first-derivative nonadiabatic couplings for the H3 system (2001)
Abrol, Ravinder, Shaw, Amy, Kuppermann, Aron, Yarkony, David R.
A conical intersection exists between the ground (1 2 A[prime]) and the first-excited (2 2A[prime]) electronic potential energy surfaces (PESs) of the H3 system for C3v geometries. This intersection...
A quantum and semiclassical study of dynamical resonances in the C + NO-->CN + O reaction (2001)
Abrol, Ravinder, Wiesenfeld, Laurent, Lambert, Bruce, Kuppermann, Aron
Accurate quantum mechanical reactive scattering calculations were performed for the collinear C+NO-->CN+O reaction using a polynomial-modified London Eyring Polanyi Sato (PQLEPS) potential energy...
A very high accuracy potential energy surface for H3 (1999)
Wu, Y.-S. Mark, Kuppermann, Aron, Anderson, James B.
An exact quantum Monte Carlo (EQMC) method was used to calculate the potential energy surface (PES) for the ground electronic state of H3 over a grid of about 76000 nuclear geometries. The absolute...
The Quantum Dynamics of Chemical Reactions. (1998)
The aim of the proposed research is the performance of quantum mechanical calculations of an exact and approximate nature of the cross sections and rate constants of elementary chemical reactions....
Experimental Studies of the Properties of Trihydrogen and Tetrahydrogen. (1998)
Results of theoretical calculations by Nicolaides et al. have suggested the existence of metastable tetrahydrogen (H4) molecules. The specific impulse of this species is estimated to be 1820 s,...
Theoretical Studies of the Lifetime of Metastable H3. (1998)
In this report, the major steps toward the ab initio determination of the lifetime (via both the radiation and the predissociation decay mechanisms) for the H3 metastable states have been identified...
Excited electronic potential-energy surfaces and transition moments for the H3 system (1995)
Peng, Zhengwei, Kristyan, Sandor, Kuppermann, Aron, Wright, James S.
Four electronic states of H3 have been studied using a multiple-reference double-excitation configuration-interaction method with an extensive basis set of 75 Gaussian-type atomic orbitals. A total...
Garvey, James F., Kuppermann, Aron
In a previous paper we reported a technique for generating an intense hyperthermal beam of hydrogen atoms and metastable H3 molecules. From the flight time of the H3 species between the source and...
Kuppermann, Aron, Hipes, Paul G.
We report here the first three-dimensional (3D) reactive scattering calculations using symmetrized hyper-spherical coordinates (SHC). They show that the 3D local hyper-spherical surface function...
Kaye, Jack A., Kuppermann, Aron
Quasiclassical trajectory calculations have been carried out at energies above the threshold for collision-induced dissociation for a model symmetric collinear atom–diatomic molecule system. Exact...
Truhlar, Donald G., Garrett, Bruce C., Hipes, Paul G., Kuppermann, Aron
We present three sets of calculations for the thermal rate constants of the collinear reaction I+HI-->IH+I: accurate quantum mechanics, conventional transition state theory (TST), and variational...
Time-resolved two-color photoacoustic and multiphoton ionization spectroscopy of aniline (1984)
The multiphoton ionization and photoacoustic signals from aniline have been detected as a function of time delay between two laser pulses of different wavelength. The first pulse excited the S0 →...
Singlet→triplet transitions in C≡N containing molecules by electron impact (1984)
Rianda, Ronald, Frueholz, Robert P., Kuppermann, Aron
The electron-impact excitation spectra of hydrogen cyanide (HCN), acetonitrile (CH3CN), malononitrile [CH2(CN)2], propionitrile (C2H5CN), and butyronitrile (C3H7CN) have been studied experimentally...
Parker, Gregory A., Keil, Mark, Kuppermann, Aron
Experimentally measured differential cross sections are presented for the interactions of He with the linear molecules CO2,N2O, and C2N2. These data show pronounced dampening of the diffraction...
Babamov, Vasil K., Kuppermann, Aron
A simple model is presented that explains the main characteristics of the low energy resonances found in accurate quantum mechanical scattering calculations of collinear reactive collisions of the...
Variable angle electron-impact excitation of nitromethane (1980)
Flicker, Wayne M., Mosher, Oren A., Kuppermann, Aron
The electron-impact excitation of nitromethane has been studied at incident electron energies of 25, 55, and 90 eV, at scattering angles from 6° to 80°. The lowest-lying inelastic process which is...
Electronic spectroscopy of benzene and the fluorobenzenes by variable angle electron impact (1979)
Frueholz, Robert P., Flicker, Wayne M., Mosher, Oren A., Kuppermann, Aron
Electron-impact spectra of benzene and 11 fluorine-substituted derivatives have been obtained at impact energies of 75, 50, and either 25 or 30 eV, and scattering angles from 5° to 80°. Each...
Frueholz, Robert P., Flicker, Wayne M., Mosher, Oren A., Kuppermann, Aron
The excited electronic states of cyclohexene, 1,4-cyclohexadiene, norbornene (bicyclo[2.2.1]-2-heptene), and norbornadiene (bicyclo-[2.2.1]-2,5-heptadiene) have been studied by electron impact at...
Frueholz, Robert P., Flicker, Wayne M., Mosher, Oren A., Kuppermann, Aron
The electronic spectra of three conjugated cis-dienyl systems, 1,3-cyclopentadiene, 1,3-cyclohexadiene, and 1,3-cycloheptadiene have been investigated using electron-impact spectroscopy. Spectra were...
Electronic spectroscopy of UF6 and WF6 by electron impact (1979)
Rianda, Ronald, Frueholz, Robert P., Kuppermann, Aron
The electron-impact excitation spectra of uranium hexafluoride (UF6) and tungsten hexafluoride (WF6) have been studied experimentally at impact energies of 30, 50, and 75 eV and at scattering angles...
Electron-impact excitation of low-lying electronic states in CS2, OCS, and SO2 (1978)
Flicker, Wayne M., Mosher, Oren A., Kuppermann, Aron
Variable angle, electron-impact energy-loss spectra of CS2, OCS, and SO2 have been obtained at incident electron energies of 25, 40, and 70 eV for CS2, and 30 and 55 eV for OCS and SO2....
Frueholz, Robert P., Kuppermann, Aron
The electron-impact energy loss spectrum of 1,3,5,7-cyclooctatetraene has been measured at electron impact energies of 30, 50, and 75 eV, and scattering angles varying from 5° to 80°. Three...
Vibronic structure of the second triplet state of 1,3,5-hexatriene (1978)
Frueholz, Robert P., Kuppermann, Aron
Electron impact spectroscopy is used to study the vibronic structive of the second triplet state of 1,3,5-hexatriene.
Doublet-->quartet transitions in nitric oxide as detected by electron-impact spectroscopy (1978)
Frueholz, Robert P., Rianda, Ronald, Kuppermann, Aron
Vibronic bands in NO are investigated using electron beam excitation. The beams had energies of 25, 35, and 50 eV.
Quantum mechanical reactive scattering for planar atom plus diatom systems. I. Theory (1976)
Kuppermann, Aron, Schatz, George C., Baer, M.
A method is presented for accurately solving the Schrödinger equation for the reactive collision of an atom with a diatomic molecule on a space-fixed plane. The procedure consists primarily of two...
Electron impact investigation of electronic excitations in furan, thiophene, and pyrrole (1976)
Flicker, Wayne M., Mosher, Oren A., Kuppermann, Aron
The electronically excited states of furan, thiophene, and pyrrole have been studied by electron impact at scattering angles from 0° to 80°, and impact energies of 30 and 50 eV. Low-lying features...
Schatz, George C., Kuppermann, Aron
We present results of one-, two-, and three-dimensional calculations for the H + H2 exchange reaction which provide the first evidence for dynamical internal excitation (Feshbach) resonances in...
Schatz, George C., Bowman, Joel M., Kuppermann, Aron
Exact quantum, quasiclassical, and semiclassical reaction probabilities and rate constants for the collinear reaction F+H2 --> FH+H are presented and compared. The exact quantum results indicate a...
Electronic spectroscopy of trans-azomethane by electron impact (1975)
Mosher, Oren A., Foster, Michael S., Flicker, Wayne M., Beauchamp, J. L., Kuppermann, Aron
The electron impact excitation of trans-azomethane (i.e., trans-dimethyl diazine CH3–N–N–CH3) has been studied by both trapped electron (TE) and differential electron scattering (DES)...
Electronic spectroscopy of propadiene (allene) by electron impact (1975)
Mosher, Oren A., Flicker, Wayne M., Kuppermann, Aron
The electron impact excitation of propadiene (allene) has been studied experimentally at impact energies of 20, 40, and 60 eV and scattering angles from 6° to 80°. Two transitions with maxima at...
Quantum mechanical reactive scattering: An accurate three-dimensional calculation (1975)
Kuppermann, Aron, Schatz, George C.
Accurate three–dimensional (3–D) quantum–mechanical calculations of differential and total cross sections for the H + H2 exchange reaction on the Porter and Karplus potential energy surface...
Abstraction fraction in the reaction of deuterium atoms with HBr and HI (1974)
Persky, Avigdor, Kuppermann, Aron
The reaction between D atoms and HX molecules (X=Br or I) may result in either abstraction of H atoms to yield HD+X or exchange of H atoms to yield DX+H. This reaction was studied at 300°K by...
Electronic spectroscopy of s-trans 1,3-butadiene by electron impact (1973)
Mosher, Oren A., Flicker, Wayne M., Kuppermann, Aron
The electron impact excitation of 1,3-butadiene has been studied experimentally at impact energies of 20, 35, and 55 eV and scattering angles from 10° to 85°. The energy and angular dependences of...
Electronic spectroscopy of s-trans 1,3-butadiene by electron impact (1973)
Mosher, Oren A., Flicker, Wayne M., Kuppermann, Aron
The electron impact excitation of 1,3-butadiene has been studied experimentally at impact energies of 20, 35, and 55 eV and scattering angles from 10° to 85°. The energy and angular dependences of...
Bowman, Joel M., Kuppermann, Aron
Using the classical (CSC), primitive (PSC), and uniform (USC) semiclassical expressions for transition probabilities given by Miller and co-workers, we have calculated the reactive and nonreactive 0...
Schatz, George C., Kuppermann, Aron
The question of the relative importance of compound state (i.e., activated complex) and direct reaction mechanisms has been of central importance for the dynamical foundations of chemical kinetics...
Truhlar, Donald G., Kuppermann, Aron, Adams, John T.
Quantum mechanical calculations on three of the collinear H+H2 reactions involving D-substitutions are presented and compared with each other and with previous calculations on the H+H2 reaction...
String-plucking model for vibrational excitation of molecules (1973)
Gordon, Robert J., Kuppermann, Aron
A "string-plucking" model has been developed to describe the translational to vibrational energy transfer between an atom and a harmonic oscillator in terms of the time-dependent force constant and...
Large quantum effects in the collinear F+H2-->FH+H reaction (1973)
Schatz, George C., Bowman, Joel M., Kuppermann, Aron
We have performed accurate quantum mechanical calculations of reaction probabilities for the collinear F+H2-->FH+H reaction as well as corresponding quasiclassical trajectory calculations. A...
Kuppermann, Aron, Gordon, Robert J., Coggiola, Michael J.
Differential elastic scattering cross sections for the systems H2+ O2, SF6, NH3, CO, and CH4 and for D2+ O2, SF6, and NH3 have been obtained from crossed beam studies. In all cases, rapid quantum...
Truhlar, Donald G., Kuppermann, Aron
We present numerical quantum mechanical scattering calculations for the collinear H+H2 reaction on a realistic potential energy surface with an 0.424 eV (9.8 kcal) potential energy barrier. The...
Detection and Identification of Triplet States of H2O by Electron Impact (1971)
Trajmar, S., Williams, W., Kuppermann, Aron
It has been previously (1-4) that the angular behavior of the differential cross section for exciting molecular electronic states by low-energy electron impact is a useful tool in distinguishing...
Truhlar, Donald G., Kuppermann, Aron
The H + H2 reaction is very important in theoretical chemical dynamics (1-4). A model that is often used to study this reaction is to restrict the atoms to lie on a nonrotating line throughout the...
Truhlar, Donald G., Rice, James K., Kuppermann, Aron, Trajmar, S., Cartwright, D. C.
Differential scattering cross sections for excitation of helium by electron impact from its ground state to its 21P excited state have been measured at four incident electron energies in the range...
Truhlar, Donald G., Cartwright, David C., Kuppermann, Aron
Several first-order methods for rearrangement collisions are compared by applying them all to the same problem: electron-exchange scattering off the hydrogen atom. The methods considered are...
Persky, Avigdor, Greene, Edwad F., Kuppermann, Aron
Yields are reported for the formation of positive and negative ions from molecular beams striking various surfaces. Negative ions are formed from beams of several halogen compounds and...
Rice, J. K., Kuppermann, Aron, Trajmar, Sandor
Optically forbidden electronic transitions can be produced by low-energy electron impact. Recent experimental investigations of helium (1-3) have shown that the differential scattering cross sections...
Argon resonance line lamp for vacuum ultraviolet photochemistry (1968)
Lane, Arthur L., Kuppermann, Aron
The use of rare gas resonance line lamps as sources of monochromatic radiation for photochemical studies is well known.(1-5) Argon is ideally suited for photoionization studies of the simpler...
Cartwright, David C., Kuppermann, Aron
Calculations for the electron-impact excitation cross sections of molecular hydrogen from its ground (X1Σg+) to its first (b3Σu+) and second (a3Σg+) triplet states were performed using the Ochkur...
Kuppermann, Aron, Belford, Geneva G.
A generalized formulation of the diffusion-kinetic model of track effects in radiation chemistry is presented and criticized. It permits consideration of complex mechanisms, arbitrary initial...
Kuppermann, Aron, Belford, Geneva G.
A generalized formulation of the diffusion-kinetic model of track effects in radiation chemistry is presented and criticized. It permits consideration of complex mechanisms, arbitrary initial...
Nonmolecular nature of nitric-oxide-inhibited thermal decomposition of n-butane (1960)
Kuppermann, Aron, Larson, John G.
The thermal decomposition of most organic molecules is generally accepted to occur at least in part via a free radical chain process. Since Hinshelwood and Staveley (1) discovered that small...
Nonmolecular nature of nitric-oxide-inhibited thermal decomposition of n-butane (1960)
Kuppermann, Aron, Larson, John G.
The thermal decomposition of most organic molecules is generally accepted to occur at least in part via a free radical chain process. Since Hinshelwood and Staveley (1) discovered that small...
Quantum-Mechanical Calculation of One-Electron Properties. I. General Formulation (1958)
Karplus, Martin, Kuppermann, Aron, Isaacson, Leonard M.
For a one-electron operator, general formulas for weighted transition functions, weighted density functions, and their integrals are introduced. A detailed treatment is given of the expressions that...