Ab initio investigation of the stationary points on the potential energy surface for the ethylene-sulfur dioxide complex

1994 ◽  
Vol 231 (2-3) ◽  
pp. 283-288 ◽  
Author(s):  
Wagner B. De Almeida
Keyword(s):  
Sulfur Dioxide ◽  
Potential Energy ◽  
Potential Energy Surface ◽  
Ab Initio ◽  
Energy Surface ◽  
Stationary Points

scholarly journals Desymmetrization in geometry optimization: application to an ab initio study of copper(I) hydration

2020 ◽  
Vol 92 (10) ◽  
pp. 1643-1654
Author(s):  
Cory C. Pye ◽  
Daniel C. M. Whynot ◽  
Christopher R. Corbeil ◽  
Darren J. W. Mercer
Keyword(s):  
Irreducible Representation ◽  
Potential Energy ◽  
Potential Energy Surface ◽  
Ab Initio ◽  
Coordination Number ◽  
Energy Surface ◽  
Geometry Optimization ◽  
Symmetry Reduction ◽  
Stationary Points ◽  
Ab Initio Study

AbstractGroup theoretical arguments are used to find the subgroup corresponding to symmetry reduction along a particular irreducible representation of a group. The results are used to guide the search for stationary points on the potential energy surface of hydrated copper(I) ion at the HF/6-31G∗, HF/6-31+G∗, HF/6-311+G∗, MP2/6-31G∗, MP2/6-31+G∗, MP2/6-311+G∗, B3LYP/6-31G∗, B3LYP/6-31+G∗, and B3LYP/6-311+G∗ levels. The better levels give the most stable coordination number of two. The effect of desymmetrization on the Cu-O distances and stretching frequencies has been examined.

CONSTRUCTION OF A GLOBAL POTENTIAL ENERGY SURFACE FROM NOVEL AB INITIO MOLECULAR DYNAMICS FOR THE O(3P) + C3H3 REACTION

2005 ◽  
Vol 04 (01) ◽  
pp. 163-173 ◽  
Author(s):  
SEUNG C. PARK ◽  
BASTIAAN J. BRAAMS ◽  
JOEL M. BOWMAN
Keyword(s):  
Molecular Dynamics ◽  
Potential Energy ◽  
Potential Energy Surface ◽  
Ab Initio ◽  
Energy Surface ◽  
Radical Reaction ◽  
Ab Initio Molecular Dynamics ◽  
Stationary Points ◽  
Permutational Symmetry ◽  
Diffusion Monte Carlo Method

We present a global potential energy surface (PES) for the 2 A state of the O (3 P ) + C 3 H 3 radical reaction. The global PES is constructed mainly using direct ab initio molecular dynamics and further sampling is done using the Diffusion Monte Carlo method. The potential is fully invariant with respect to permutational symmetry of like atoms. Special techniques, based on invariant theory of finite groups, have been used to develop basis functions for fitting that display this symmetry. The resultant potential energy surface shows multiple reaction paths with six different product channels. The products of the reactions are CO + C 2 H 3 radicals H + C 3 H 2 O radicals (with two isomers, propynal and propa-1,2-dien-1-one) and OH + C 3 H 2 radicals (with three isomers, vinylidenecarbene, propargylene and cyclopropenylidene). Energies of the PES are in excellent agreement with ab initio energies for each stationary point, the reactants and the products. Most stationary points are fitted at the sub Kcal/mol level. The global potential surface represents all the stationary points and six different product channels correctly. Preliminary dynamics calculations show abstraction and insertion mechanisms for the OH + vinylidenecarbene channel and the H + propynal channel, respectively.

Sign in / Sign up

Export Citation Format

Share Document