Optimization of equilibrium geometries and transition structures

Journal of Computational Chemistry - Tập 3 Số 2 - Trang 214-218 - 1982
H. Bernhard Schlegel1
1Dept. of Chemistry, Wayne State University, Detroit, Michigan 48202

Tóm tắt

AbstractA modified conjugate gradient algorithm for geometry optimization is outlined for use with ab initio MO methods. Since the computation time for analytical energy gradients is approximately the same as for the energy, the optimization algorithm evaluates and utilizes the gradients each time the energy is computed. The second derivative matrix, rather than its inverse, is updated employing the gradients. At each step, a one‐dimensional minimization using a quartic polynomial is carried out, followed by an n‐dimensional search using the second derivative matrix. By suitably controlling the number of negative eigenvalues of the second derivative matrix, the algorithm can also be used to locate transition structures. Representative timing data for optimizations of equilibrium geometries and transition structures are reported for ab initio SCFMO calculations.

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Tài liệu tham khảo

10.1007/978-1-4684-8541-7_4

Pople J. A., 1979, Int. J. Quantum Chem., 13, 225

10.1063/1.439657

10.1063/1.439707

10.1016/0009-2614(79)80117-7

10.1080/00268976900100941

10.1063/1.1727068

Bratoz S., 1958, Coll. Int. C.N.R.S., 82, 287

Binkley J. S., 1980, GAUSSIAN 80, An Ab Initio Molecular Orbital Program

Fletcher R., 1972, Numerical Methods for Unconstrained Optimization

10.1007/BF00927440

10.1093/comjnl/13.2.185

10.1016/0009-2614(71)80294-4

10.1016/0097-8485(78)80005-9

10.1063/1.431089

D.GartonandB. T.Sutcliffe inSpecialist Periodical Report Theoretical Chemistry N. Dixon Sr. Reporter Chemical Society London 1974.

Brodlie K. W., 1977, Math. Prog., 12, 344, 10.1007/BF01593802

W. J.Hehre W. A.Lathan R.Ditchfield M. D.Newton andJ. A.Pople GAUSSIAN70 Program No. 236 Quantum Chemistry Program Exchange Indiana University Bloomington IN 1973.

10.1063/1.1749433

1935, J. Chem. Phys., 3, 227

H. B.Schlegel unpublished.

Whiteside R. A., 1980, Carnegie‐Mellon Quantum Chemistry Archive

Müller K., 1980, Angew. Chem. (Int. Ed. Engl.), 19, 1, 10.1002/anie.198000013

10.1007/BF00547608