Showing papers on "Potential energy surface published in 1969"
TL;DR: In this paper, a single-particle potential appropriate for the description of the nuclear fission process has been investigated, which is based on a two-centre harmonic oscillator and includes the proper boundary condition for the ground state of the fissioning nucleus as well as for the two separated fragments.
104 citations
TL;DR: In this paper, a three-dimensional classical trajectory calculation of the dynamics of the reaction D+H+H2→DH + H+H 2→DH+H + H + H 2 has been made, where the potential energy surface was obta...
Abstract: A three-dimensional classical trajectory calculation has been made of the dynamics of the reaction D+ + H2 → DH + H+. In contrast to earlier trajectory studies the potential-energy surface was obta...
62 citations
TL;DR: In this article, the structure of the bicyclo [2.2]-octane (BCO) skeleton has been solved with the help of direct methods and refined by full-matrix least-squares analysis of the three-dimensional intensity data.
Abstract: Crystals of bicyclo [2.2.2] octane-1, 4-dicarboxylic acid are monoclinic, a = 6.01 A, b = 16.73 A, c = 10.29 A, β = 115.08°, space group P21/c, with 4 molecules in the unit cell. The structure was solved with the help of direct methods and refined by full-matrix least-squares analysis of the three-dimensional intensity data. Within experimental error the bicyclo [2.2.2]-octane (BCO) skeleton has apparent D3h-symmetry, corresponding to the totally eclipsed conformation. Analysis of the thermal ellipsoids in terms of the translational and rotational motion of the BCO skeleton leads to an r.m.s. amplitude of 5.9 ± 0.2° for rotation about the threefold axis.
On the assumption that the bond lengths remain effectively constant during a torsional vibration of BCO, the potential energy surface has been calculated for a range of semi-empirical potential functions. These calculations show that the energy minimum may be slightly displaced from D3h symmetry, but if so the barrier between the two such equivalent minima is only about 0.1 kcal mole−1. The energy eigenvalues and eigenfunctions for a typical variation of potential energy vs torsion angle have been calculated. From the form of the eigenfunction of the ground vibrational state we conclude that BCO has effective D3h symmetry at all temperatures as far as diffraction methods are concerned.
50 citations
TL;DR: In this article, a model for the reaction CH3 is studied including the hybridization change of the reaction center, and a potential energy surface is constructed, giving a saddle point value close to the experimental activation energy.
Abstract: A model for the reaction CH3.+CH2=CH2 is studied including the hybridization change of the reaction center. The interaction energy is devided into two parts. The first is a stabilization energy — the contribution due to the π-electron delocalization (including the hybridization effects). It is computed by the PPP method. The second part is an exchange repulsion due to all valence electrons of the three carbon atoms. Correlation corrections are considered. A potential energy surface is constructed, giving a saddle point value close to the experimental activation energy. A discussion is given of the approximations involved. The method suggested is a generalization of the reactivity indices method of the theory of chemical reactivity. It can be regarded as a justification of this more empirical approach.
14 citations