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Electrostatic energies charges

In periodic boimdary conditions, one possible way to avoid truncation of electrostatic interaction is to apply the so-called Particle Mesh Ewald (PME) method, which follows the Ewald summation method of calculating the electrostatic energy for a number of charges [27]. It was first devised by Ewald in 1921 to study the energetics of ionic crystals [28]. PME has been widely used for highly polar or charged systems. York and Darden applied the PME method already in 1994 to simulate a crystal of the bovine pancreatic trypsin inhibitor (BPTI) by molecular dynamics [29]. [Pg.369]

In this model of electrostatic in teraction s, two atoms (i and j) have poin t charges tq and qj. The magnitude of the electrostatic energy (V[. , [ ) varies inversely with the distance between the atoms, Rjj. fh e effective dielectric constant is . For in vacuo simulations or simulation s with explicit water rn olecules, the den om in a tor equals uRjj, In some force fields, a distance-dependent dielectric, where the denominator is uRjj Rjj, represen is solvent implicitly. [Pg.27]

In the generalised Born approach the total electrostatic energy is written as a sum of tin terms, the first of which is the Coulomb interaction between the charges in vacuo ... [Pg.615]

A. rather complex procedure is used to determine the Born radii a values of which. calculated for each atom in the molecule that carries a charge or a partial charge. T Born radius of an afom (more correctly considered to be an effective Born radii corresponds to the radius that would return the electrostatic energy of the system accordi to the Bom equation if all other atoms in the molecule were uncharged (i.e. if the other ato only acted to define the dielectric boundary between the solute and the solvent). In Sti force field implementation, atomic radii from the OPLS force field are assigned to ec... [Pg.615]

Transition state is more polar than starting state polar solvent can cluster about transition state so as to reduce electrostatic energy associated with separation of opposite charges... [Pg.346]

The electrostatic energy is then calculated for this system of charge [2], giving... [Pg.233]

The Electrical A nalogue of Magnetic Cooling. Three Processes bg Which Ions Are Introduced into Solution.. 1 Polar Dielectric in an Electrostatic Field. The Concepts of Faraday and Maxwell. The Electrostatic Energy in the Fields of Ions. The. Charging of a Condenser. The Amount of Free Energy Lost, by a Dielectric. The Behavior of Solvents in an Electrostatic Field. A Dielectric in the Field of a Charged Sphere. Two Types of Process Contrasted. [Pg.1]

The Electrostatic Energy. In Chapter 2 we drew attention to the fact that, when a proton transfer (117) has been carried out in a solvent, the electrostatic fields of two ions have been created and work must have been done to supply the amount of energy associated with these ionic fields. Let us now compare (117) with the process (123), both in aqueous solution at the same temperature. In both cases an (HaO)+ ion will be formed but in (123), when the proton is removed from the (IIS04)-ion, we have to separate the particles against the mutual attraction of the proton and the doubly charged ion (S04)". Consequently, more work must be done against the electrostatic forces of attraction than in the removal of a proton from a neutral particle. [Pg.116]

As discussed in the early sections it seems that there are very few effective ways to stabilize the transition state and electrostatic energy appears to be the most effective one. In fact, it is quite likely that any enzymatic reaction which is characterized by a significant rate acceleration (a large AAgf +p) will involve a complimentarity between the electrostatic potential of the enzyme-active site and the change in charges during the reaction (Ref. 10). This point may be examined by the reader in any system he likes to study. [Pg.226]

This can be done when TV = TV which implies that q+ = q. = 0 for an overall neutral system, i.e. TV = TV = 0. But note that even for an overall charged system, i.e. a system where a net charge q has been introduced via, e.g. a van de Graaf machine, the excess electrostatic energy is ... [Pg.221]

The non-zero, in general, value of e Pw-e PR in Equation (7.18) implies that there are net surface charges on the gas exposed electrode surfaces. These charges (q+,q.) have to be opposite and equal as the cell is overall electrically neutral and all other charges are located at the metal-solid electrolyte interfaces to maintain their electroneutrality. The charges q+=-q. are quite small in relation to the charges, Q, stored at the metal-electrolyte interface but nevertheless the system has, due to their presence, an excess electrostatic energy ... [Pg.349]


See other pages where Electrostatic energies charges is mentioned: [Pg.40]    [Pg.40]    [Pg.180]    [Pg.345]    [Pg.148]    [Pg.216]    [Pg.220]    [Pg.623]    [Pg.175]    [Pg.174]    [Pg.92]    [Pg.93]    [Pg.98]    [Pg.402]    [Pg.443]    [Pg.50]    [Pg.63]    [Pg.18]    [Pg.131]    [Pg.9]    [Pg.65]    [Pg.119]    [Pg.125]    [Pg.149]    [Pg.232]    [Pg.179]    [Pg.165]    [Pg.123]    [Pg.125]    [Pg.77]    [Pg.71]    [Pg.71]    [Pg.183]    [Pg.165]    [Pg.487]    [Pg.243]   


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