Reactive empirical bond order

Reactive empirical bond order

The reactive empirical bond-order (REBO) model is a widely-used function for calculating the potential energy of covalent bonds and the interatomic force. In this model, the total potential energy of system is a sum of nearest-neighbour pair interactions which depend not only on the distance between atoms but also on their local atomic environment. A parameterized bond order function was used to describe chemical pair bonded interactions.

The early formulation and parametrization of REBO for carbon systems was done by Tersoff in 1988 [1, 2] , based on works of Abell [3] . The Tersoff’s model could describe single, double and triple bond energies in carbon structures such as in hydrocarbons and diamonds. A significant step was taken by Brenner in 1990 [4, 5] . He extended Tersoff’s potential function to radical and conjugated hydrocarbon bonds by introducing two additional terms into the bond order function.

Compared to classical first-principle and semi-empirical approaches, the REBO model is less time-consuming, since only the 1st- and 2nd-nearest-neighbour interactions were considered. This advantage of computational efficiency is especially helpful for large-scale atomic simulations (from 1000 to 1000000 atoms) [6] . In recent years, the REBO model has been widely used in the studies concerning mechanical and thermal properties of Carbon nanotubes [7, 8] .

Despite numerous successful applications of the first-generation REBO potential function, its several drawbacks have been reported. e.g. its form is too restrictive to simultaneously fit equilibrium distances, energies, and force constants for all types of C-C bonds, the possibility of modeling processes involving energetic atomic collisions is limited because both Morse-type terms go to finite values when the atomic distance decreases, and the neglect of a separate pi bond contribution leads to problems with the overbinding of radicals and a poor treatment of conjugacy [9, 10] .

In order to overcome these drawbacks, an extension of Brenner’s potential was proposed by Stuart et al. [10] . It is called the adaptive intermolecular reactive bond order (AIREBO) potential, in which both the repulsive and attractive pair interaction functions in REBO function are modified to fit bond properties, and the long-range atomic interactions and single bond torsional interactions are included. The AIREBO model has been used in recent studies using numerical simulations [11, 12] .

References

[1] J. Tersoff, Phys. Rev. B 37, 6991 (1988).

[2] J. Tersoff, Phys. Rev. Lett. 61, 2879 (1988).

[3] G. Abell, Phys. Rev. B 31, 6184 (1985).

[4] D. W. Brenner Phys. Rev. B 42, 9458 (1990).

[5] D. Brenner, Phys. Rev. B 46, 1948 (1992).

[6] D. Brenner, Physica Status Solidi (B) 217, 23 (2000).

[7] R. Ruoff, D. Qian, and W. Liu, C. R. Physique 4, 993 (2003).

[8] H. Rafii-Tabar, Physics Reports 390, 235 (2004).

[9] D. Pettifor and I. Oleinik, Phys. Rev. B 59, 8487 (1999).

[10] S. J. Stuart et al, J. Chem. Phys. 112, 6472 (2000).

[11] B. Ni et al, Phys. Rev. Lett. 88, 2055051 (2002).

[12] A. Nikitin et al, Phys. Rev. Lett. 95, 225507 (2005).


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • Resonance (chemistry) — For other uses, see Resonance (disambiguation). Two of the contributing structures of nitrogen dioxide In chemistry, resonance or mesomerism [1] is a way of describing delocalized electrons within certain molecules or …   Wikipedia

  • Molecular dynamics — (MD) is a computer simulation of physical movements of atoms and molecules. The atoms and molecules are allowed to interact for a period of time, giving a view of the motion of the atoms. In the most common version, the trajectories of molecules… …   Wikipedia

  • Oxygen — This article is about the chemical element and its most stable form, O2 or dioxygen. For other forms of this element, see Allotropes of oxygen. For other uses, see Oxygen (disambiguation). nitrogen ← oxygen → fluorine ↑ O ↓ …   Wikipedia

  • Attachment theory — …   Wikipedia

  • Force field (chemistry) — In the context of molecular mechanics, a force field (also called a forcefield) refers to the functional form and parameter sets used to describe the potential energy of a system of particles (typically but not necessarily atoms). Force field… …   Wikipedia

  • Attachment therapy — This article is about a specific form of therapy commonly known as attachment therapy . For therapies based on Bowlby s attachment theory, see Attachment based therapy (children). Attachment therapy is the most commonly used term for a… …   Wikipedia

  • Physical Sciences — ▪ 2009 Introduction Scientists discovered a new family of superconducting materials and obtained unique images of individual hydrogen atoms and of a multiple exoplanet system. Europe completed the Large Hadron Collider, and China and India took… …   Universalium

  • chemistry — /kem euh stree/, n., pl. chemistries. 1. the science that deals with the composition and properties of substances and various elementary forms of matter. Cf. element (def. 2). 2. chemical properties, reactions, phenomena, etc.: the chemistry of… …   Universalium

  • Silicon — Not to be confused with the silicon containing synthetic polymer silicone. aluminium ← silicon → phosphorus C ↑ Si ↓ Ge …   Wikipedia

  • dye — dyable, dyeable, adj. dyer, n. /duy/, n., v., dyed, dyeing. n. 1. a coloring material or matter. 2. a liquid containing coloring matter, for imparting a particular hue to cloth, paper, etc. 3. color or hue, esp. as produced by dyeing. 4. of the… …   Universalium

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”