CIVIL PRACTICE Nonjury Trials: Require Parties to Move for Written Findings of Fact and Conclusions of Law

The Act Amends the Georgia Civil Practice Act to require parties in nonjury trials to request or move for written findings of fact and conclusions of law by the court. The parties\u27 failure to do so results in a waiver for purposes of appellate review. July 1, 198

Test of variational transition state theory against accurate quantal results for a reaction with very large reaction-path curvature and a low barrier

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 transition state theory (VTST). This reaction differs from previous test cases in that it has very large reaction-path curvature but hardly any tunneling. TST overestimates the accurate results by factors of 2×10^10, 2×10^4, 57, and 19 at 40, 100, 300, and 1000 K, respectively. At these same four temperatures the ratios of the VTST results to the accurate quantal ones are 0.3, 0.8, 1.1, and 1.4, respectively. We conclude that the variational transition states are meaningful, even though they are computed from a reaction-path Hamiltonian with large curvature, which is the most questionable case

Studies of Electron-Molecule Collisions on the Mark IIIfp Hypercube

We report on a distributed memory implementation and initial applications of a program for calculating electron-molecule collision cross sections. Runs on the Mark IIIfp hypercube show that large-grain MIMD machines are well suited for these applications. Some results of studies of e^--Si_2H_6 and e^--SiF_4 collisions will be discussed

Three Dimensional Atom-Diatom Reactive Scattering Calculations Using Symmetrized Hyperspherical Coordinates

The focus of this thesis is the use of symmetrized hyperspherical coordinate techniques in the accurate calculation of differential cross sections for the reactive collision of an atom with a diatomic molecule in three-dimensional space. A single set of symmetrized hyperspherical coordinates treats all regions of configuration space in an equivalent inelastic scattering problem which is conceptually and computationally easier to handle. The work described here represents the first successful application of any accurate hyperspherical coordinate methodology to atom-diatom reactive scattering in three-dimensional space. This methodology has permitted the calculation of zero total angular momentum (J = 0) partial wave transition probabilities and associated phases over a significantly larger range of collision energies (up to 1.6 eV total energy) than previously possible for the system H + H₂. The numerical stability of the treatment is sufficiently high to permit the first lifetime matrix analysis of the resonance structure of H + H₂ based on scattering matrices from our accurate calculations. This analysis reveals a series of 6 resonance states in the J = 0 partial wave, some of which have not been seen before. The symmetrized hyperspherical coordinate methodology is presented in detail. A selection of surface functions and scattering results for J = 0 H + H₂ using the LSTH potential energy surface are presented and discussed. In addition, a small number of results from the Porter-Karplus potential energy surface are also given.</p

Studies of electron collisions with polyatomic molecules using distributed-memory parallel computers

Elastic electron scattering cross sections from 5–30 eV are reported for the molecules C_2H_4, C_2H_6, C_3H_8, Si_2H_6, and GeH_4, obtained using an implementation of the Schwinger multichannel method for distributed‐memory parallel computer architectures. These results, obtained within the static‐exchange approximation, are in generally good agreement with the available experimental data. These calculations demonstrate the potential of highly parallel computation in the study of collisions between low‐energy electrons and polyatomic gases. The computational methodology discussed is also directly applicable to the calculation of elastic cross sections at higher levels of approximation (target polarization) and of electronic excitation cross sections

Studies of electron-molecule collisions on distributed-memory parallel computers

We review recent progress in the study of low-energy collisions between electrons and polyatomic molecules which has resulted from the application of distributed-memory parallel computing to this challenging problem. Recent studies of electronically elastic and inelastic scattering from several molecular systems, including ethene, propene, cyclopropane, and disilane, are presented. We also discuss the potential of ab initio methods combined with cost-effective parallel computation to provide critical data for the modeling of materials-processing plasmas

Studies Of Electron Collisions With Polyatomic Molecules Using Distributed-memory Parallel Computers

Elastic electron scattering cross sections from 5-30 eV are reported for the molecules C2H4, C2H6, C 3H8, Si2H6, and GeH4, obtained using an implementation of the Schwinger multichannel method for distributed-memory parallel computer architectures. These results, obtained within the static-exchange approximation, are in generally good agreement with the available experimental data. These calculations demonstrate the potential of highly parallel computation in the study of collisions between low-energy electrons and polyatomic gases. The computational methodology discussed is also directly applicable to the calculation of elastic cross sections at higher levels of approximation (target polarization) and of electronic excitation cross sections. © 1991 American Institute of Physics.9485455546