scispace - formally typeset
Search or ask a question
Topic

Potential energy surface

About: Potential energy surface is a research topic. Over the lifetime, 11674 publications have been published within this topic receiving 307691 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: In this article, an aluminosilicate cluster model containing five tetrahedral (Si, Al) atoms (5T) was used to locate all of the stationary points along a reaction path for ethane cracking at the HF/6-31G(d), B3LYP/6 -31G (d), and MP2(FC)/6- 31G(D) levels of theory.
Abstract: Protolytic cracking of ethane in zeolites has been investigated using quantum-chemical techniques and a cluster model of the zeolite acid site. An aluminosilicate cluster model containing five tetrahedral (Si, Al) atoms (5T) was used to locate all of the stationary points along a reaction path for ethane cracking at the HF/6-31G(d), B3LYP/6-31G(d), and MP2(FC)/6-31G(d) levels of theory. The cracking reaction occurs via a protonated structure that is a carbonium-like ion and is a transition state on the potential energy surface. The activation barrier for cracking calculated at each level of theory was refined by including (i) vibrational energies at the experimental reaction temperature of 773 K, (ii) electron correlation and/or an extended basis set at the B3LYP/6-311+G(3df,2p) or MP2(FC)/6-311+G(3df,2p) levels, and (iii) the influence of the surrounding zeolite lattice from a 58T cluster model of the zeolite H-ZSM-5. The barrier is especially sensitive to the long-range electrostatic effect of the latti...

103 citations

Journal ArticleDOI
TL;DR: In this article, a new potential energy surface of methane was constructed using extended ab initio CCSD(T) calculations at 19.882 points, and its analytical representation was determined through an expansion in symmetry adapted products of orthogonal coordinates involving 276 parameters up to 8th order with the equilibrium bond re-= 1.08601± 0.00004 A and four quadratic parameters scaled to experimental fundamental vibration frequencies.

103 citations

Journal ArticleDOI
TL;DR: In this paper, a model for the vibrational states of atom-asymmetric top van der Waals complexes is developed, based on hindered rotation of the asymmetric top in the complex.
Abstract: A model for the vibrational states of atom–asymmetric top van der Waals complexes is developed, based on hindered rotation of the asymmetric top in the complex. The pattern of energy levels expected from such a model is described, and the dependence of the spectrum on features of the potential energy surface is explored. The selection rules arising from the model are presented. The model is used to interpret the infrared spectra of Ar–H2O reported by Cohen et al. [J. Chem. Phys. 89, 4494 (1988)], and preliminary information on the effective bending potential for Ar–H2O is obtained. The potential is very isotropic, varying by only about 40 cm−1 as a function of the angular coordinates. Predictions of band origins for other allowed infrared transitions are given.

103 citations

Journal ArticleDOI
TL;DR: In this article, a successful analytic fit of the ab initio potential energy surface of McLaughlin and Thompson for the ground state HeH+2 system and also the results of a three-dimensional quasiclassical trajectory study of the exchange reaction over a wide range of vibrational states and relative translational energies of the reactants were reported.
Abstract: We report herein a successful analytic fit of the ab initio potential‐energy surface of McLaughlin and Thompson for the ground state HeH+2 system and also the results of a three‐dimensional quasiclassical trajectory study of the exchange reaction over a wide range of vibrational states and relative translational energies of the reactants. While there is good agreement between theory and experiment in many respects, there are some quantitative discrepancies remaining with respect to some of the experimental results.

103 citations


Network Information
Related Topics (5)
Ab initio
57.3K papers, 1.6M citations
95% related
Excited state
102.2K papers, 2.2M citations
89% related
Ground state
70K papers, 1.5M citations
88% related
Density functional theory
66.1K papers, 2.1M citations
86% related
Raman spectroscopy
122.6K papers, 2.8M citations
84% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023128
2022206
2021288
2020322
2019295
2018310