Browsing by Author "Senese, Frederick A."

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    An Alternative to Full Configuration Interaction Based on a Tensor Product Decomposition
    Senese, Frederick A.; Beattie, Christopher A.; Schug, John C.; Viers, Jimmy W.; Watson, Layne T. (Department of Computer Science, Virginia Polytechnic Institute & State University, 1989)
    A new direct full variational approach exploits a tensor (Kronecker) product decompositions of the Hamiltonian. Explicit assembly and storage of the Hamiltonian matrix is avoided by using the Kronecker product structure to form matrix-vector products directly from the molecular integrals. Computation-intensive integral transformations and formula tapes are unnecessary. The wave function is expanded in terms of spin-free primitive sets rather than Slater determinants or configuration state functions and is equivalent to a full configuration interaction expansion. The approach suggests compact storage schemes and algorithms which are naturally suited to parallel and pipelined machines.
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    A Full Variational Calculation Based on a Tensor ProductDecomposition
    Senese, Frederick A.; Beattie, Christopher A.; Schug, John C.; Viers, Jimmy W.; Watson, Layne T. (Department of Computer Science, Virginia Polytechnic Institute & State University, 1989)
    A new direct full variational approach exploits a tensor (Kronecker) product decomposition of the Hamiltonian. Explicit assembly and storage of the Hamiltonian matrix is avoided by using the Kronecker product structure to form matrix-vector products directly from the molecular integrals. Computation-intensive integral transformations and formula tapes are unnecessary. The wavefunction is expanded in terms of spin-free primitive kets rather than Staler determinants of configuration state functions, and the expansion is equivalent to a full configuration interaction expansion. The approach suggests compact storage schemes and algorithms which are naturally suited to parallel and pipelined machines.
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    A tensor product decomposition of the many-electron Hamiltonian
    Senese, Frederick A. (Virginia Polytechnic Institute and State University, 1989)
    A new direct full variational approach is described. The approach exploits a tensor (Kronecker) product construction of the many-electron Hamiltonian and has a number of computational advantages. Explicit assembly and storage of the Hamiltonian matrix is avoided by using the Kronecker product structure to form matrix-vector products directly from the molecular integrals. Computation-intensive integral transformations and formula tapes are unnecessary. The wavefunction is expanded in terms of spin-free primitive kets rather than Slater determinants or configuration state functions and is equivalent to a full configuration interaction expansion. The approach suggests compact storage schemes and algorithms which are naturally suited to parallel and pipelined machines. Sample calculations for small two- and four-electron systems are presented. The preliminary ground state potential energy surface of the hydrogen molecule dimer is computed by the tensor product method using a small basis set.