scholarly journals Double-well potential energy surface in the interaction between h-BN and Ni(111)

2019 ◽  
Vol 21 (21) ◽  
pp. 10888-10894
Author(s):  
Jorge Ontaneda ◽  
Francesc Viñes ◽  
Francesc Illas ◽  
Ricardo Grau-Crespo
Keyword(s):  
Density Functional Theory ◽  
Potential Energy ◽  
Density Functional ◽  
Energy Surface ◽  
Density Functional Theory Calculations ◽  
Dispersion Forces ◽  
Local Correlation ◽  
Functional Theory ◽  
Non Local ◽  
Double Well Potential

Density functional theory calculations with non-local correlation functionals, properly accounting for dispersion forces, predict the presence of two minima in the interaction energy between h-BN and Ni(111).

THE H2NO POTENTIAL ENERGY SURFACE EXPLORED WITH HIGH LEVEL AB INITIO AND DENSITY FUNCTIONAL THEORY METHODS

2007 ◽  
Vol 06 (03) ◽  
pp. 549-562
Author(s):  
ABRAHAM F. JALBOUT
Keyword(s):  
Density Functional Theory ◽  
Potential Energy ◽  
Potential Energy Surface ◽  
Density Functional ◽  
Energy Surface ◽  
Hybrid Methods ◽  
Transition States ◽  
Basis Set ◽  
Functional Theory ◽  
High Level

The transition states for the H 2 NO decomposition and rearrangements mechanisms have been explored by the CBS-Q method or by density functional theory. Six transition states were located on the potential energy surface, which were explored with the Quadratic Complete Basis Set (CBS-Q) and Becke's one-parameter density functional hybrid methods. Interesting deviations between the CBS-Q results and the B1LYP density functional theory lead us to believe that further study into this system is necessary. In the efforts to further assess the stabilities of the transition states, bond order calculations were performed to measure the strength of the bonds in the transition state.

The Variediene-Forming Carbocation Cyclization/Rearrangement Cascade

2017 ◽  
Vol 70 (4) ◽  
pp. 362 ◽  
Author(s):  
Young J. Hong ◽  
Dean J. Tantillo
Keyword(s):  
Density Functional Theory ◽  
Potential Energy ◽  
Potential Energy Surface ◽  
Density Functional ◽  
Energy Surface ◽  
Functional Theory ◽  
Density Functional Theory Computations

An energetically viable (on the basis of results from density functional theory computations) pathway to the diterpene variediene is described. Only one of the three secondary carbocations along this pathway is predicted to be a minimum on the potential energy surface.

scholarly journals Using a monomer potential energy surface to perform approximate path integral molecular dynamics simulation of ab initio water at near-zero added cost

2019 ◽  
Vol 21 (1) ◽  
pp. 409-417 ◽  
Author(s):  
Daniel C. Elton ◽  
Michelle Fritz ◽  
Marivi Fernández-Serra
Keyword(s):  
Molecular Dynamics ◽  
Density Functional Theory ◽  
Molecular Dynamics Simulation ◽  
Potential Energy ◽  
Path Integral ◽  
Liquid Water ◽  
Density Functional ◽  
Energy Surface ◽  
Dynamics Simulation ◽  
Functional Theory

We present a new approximate method for doing path integral molecular dynamics simulation with density functional theory and show the utility of the method for liquid water.

Correlation between bowl-inversion energy and bowl depth in substituted sumanenes

2014 ◽  
Vol 86 (5) ◽  
pp. 747-753 ◽  
Author(s):  
Binod Babu Shrestha ◽  
Sangita Karanjit ◽  
Shuhei Higashibayashi ◽  
Hidehiro Sakurai
Keyword(s):  
Density Functional Theory ◽  
Potential Energy ◽  
Density Functional ◽  
Theoretical Calculations ◽  
Two Dimensional ◽  
Functional Theory ◽  
Energy Diagram ◽  
Exchange Spectroscopy ◽  
Potential Energy Diagram ◽  
Double Well Potential

AbstractThe correlation between the bowl-inversion energy and the bowl depth for sumanenes monosubstituted with an iodo, formyl, or nitro group was investigated experimentally and by theoretical calculations. The bowl-inversion energies of the substituted sumanenes were determined experimentally by two-dimensional NMR exchange spectroscopy measurements. Various density functional theory methods were examined for the calculation of the structure and the bowl-inversion energy of sumanene, and it was found that PBE0, ωB97XD, and M06-2X gave better fits of the experimental value than did B3LYP. The experimental value was well reproduced at these levels of theory. The bowl structures and bowl-inversion energies of monosubstituted sumanenes were therefore calculated at the ωB97XD/6-311+G(d,p) level of theory. In both the experiments and the calculations, the correlation followed the equation ΔE = acos4 θ, where a is a coefficient, ΔE is the bowl-inversion energy, and cos θ is the normalized bowl depth, indicating that the bowl inversion follows a double-well potential energy diagram.

scholarly journals Calculation of the Detonation State of HN3 with Quantum Accuracy

2020 ◽  
Author(s):  
Cong Huy Pham ◽  
Rebecca Lindsey ◽  
Laurence E. Fried ◽  
Nir Goldman
Keyword(s):  
Molecular Dynamics ◽  
Density Functional Theory ◽  
Potential Energy ◽  
Force Field ◽  
Density Functional ◽  
Energy Surface ◽  
Detonation Properties ◽  
Training Set ◽  
Functional Theory ◽  
Wide Range

<div>HN<sub>3</sub> is a unique liquid energetic material that exhibits ultrafast detonation chemistry and a transition to metallic states during detonation. We combine the ChIMES many-body reactive force field and the extended-Lagrangian multiscale shock technique (MSST) molecular dynamics method to calculate the detonation properties of HN<sub>3</sub> with the accuracy of Kohn-Sham density-functional theory. ChIMES is based on a Chebyshev polynomial expansion and can accurately reproduce density-functional theory molecular dynamics (DFT-MD) simulations for a wide range of unreactive and decomposition conditions of liquid HN<sub>3</sub>. We show that addition of random displacement configurations and the energies of gas-phase equilibrium products in the training set allows ChIMES to efficiently explore the complex potential energy surface. Schemes for selecting force field parameters and the inclusion of stress tensor and energy data in the training set are examined. Structural and dynamical properties, as well as chemistry predictions for the resulting models are benchmarked against DFT-MD. We demonstrate that the inclusion of explicit four-body energy terms is necessary to capture the potential energy surface across a wide range of conditions. The present force field, which was fit to a balance of forces, energies, and stress tensors yields excellent agreement with DFT, while exhibiting an orders-of-magnitude increase in computational efficiency over DFT-MD. Our results generally retain the accuracy of DFT-MD while yielding a high degree of computational efficiency, allowing simulations to approach orders of magnitude larger time and spatial scales. The techniques and recipes for MD model creation we present allow for direct simulation of nanosecond shock compression experiments and calculation of the detonation properties of materials with the accuracy of Kohn-Sham density-functional theory.</div>

Sign in / Sign up

Export Citation Format

Share Document