Energy gradients in extended Hückel theory: Application to cyclopentane
作者： T. R. Ferguson , C. L. Beckel
DOI: 10.1063/1.1680275
关键词: Hückel method 、 Cyclopentane 、 Molecular physics 、 Amplitude 、 Molecular orbital 、 Computational chemistry 、 Bond length 、 Planarity testing 、 Chemistry 、 Pseudorotation 、 Degrees of freedom (physics and chemistry) 、 Physical and Theoretical Chemistry 、 General Physics and Astronomy
摘要: An energy gradient method for determining stable molecular configurations using extended Huckel theory is applied to cyclopentane. Bond lengths are constrained. Models with as many twenty‐five degrees of freedom studied, results showing that past assumptions concerning C–H bond orientations reasonable. Free pseudorotation predicted. Computed puckering amplitudes (0.40–0.47 A) and the barrier planarity (4–14 kcal/mole) compared other published results. Comparisons between orbitals in planar puckered forms indicate dominant factor eclipsing.
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