Equilibrium dissociation energy

U R) curve of a diatomic molecule, where the molecule s equilibrium dissociation energy D, is... 

The (total) ground-state dissociation energy Dq of a molecule is the energy needed to dissociate the molecule in its ground vibrational state to atoms in their ground states. Dq differs from the equilibrium dissociation energy by the zero-point... 

This is called a Morse curve, the equilibrium dissociation energy, and a the Morse range parameter. More complicated analytic forms with more parameters are also used. 

Here, Do represents the equilibrium dissociation energy and or is a parameter related to the vibrational force constant. Figure 3 provides a comparison of the two potential functions used to describe the carbon-hydrogen bond stretch based on the Dauber-Osguthorpe et al. (1988) forcefield parameters. Although both represent the equilibrium... 

Table I also lists, again for the three best ab initio studies, the equilibrium dissociation energy (De), zero point change upon association (AZPE), ground-state...

TABLE 11-9 Calculated Equilibrium Bond Lengths, Harmonic Vibrational Frequencies, and Equilibrium Dissociation Energies for the Gronnd States of H2 and N2 with the cc-pVTZ Basis Set Compared to Experiment... 

Fig. 5 Left Equilibrium structures and equilibrium dissociation energies (in cm ) for complexes of CsH with L = N2 and CO2. CCSD(T)-F12a and a combination of the basis sets cc-pVTZ-F12 (C3H+) and aug-cc-pVQZ-F12 (ligands) was used. Right Infrared photodissociation (IRPD) spectra of L dimers recorded in the C3HJ fragment channel. The...

The bond dissociation energy of the hydrogen-fluorine bond in HF is so great that the above equilibrium lies to the left and hydrogen fluoride is a weak acid in dilute aqueous solution. In more concentrated solution, however, a second equilibrium reaction becomes important with the fluoride ion forming the complex ion HFJ. The relevant equilibria are ... 

The basic thermodynamic data for the design of such reactions can be used to assess the dissociation energies for various degrees of dissociation, and to calculate, approximately, tire relevant equilibrium constants. One important source of dissociation is by heating molecules to elevated temperamres. The data below show the general trend in the thermal dissociation energies of a number of important gaseous molecules. 

Figure S-1. Form of a potential energy curve for diatomic molecule AB. VfrAa) is the potential energy, Tab is the intemuclear distance, is the equilibrium intemuclear distance, and D is the bond dissociation energy. (The zero point energy is neglected in the figure.)...

The standard heats of formation AH of gaseous HX diminish rapidly with increase in molecular weight and HI is endothermic. The very small (and positive) value for the standard free energy of formation AGj of HI indicates that (under equilibrium conditions) this species is substantially dissociated at room temperature and pressure. However, dissociation is slow in the absence of a catalyst. The bond dissociation energies of HX show a similar trend from the very large value of 574kJmol for HF to little more than half this (295kJmol ) for HI. 

There is very little experimental data available for H2", apart from the dissociation energy and equilibrium bond distance. 

Once the calculation is done, we get a better prediction of the equilibrium bond length and dissociation energy, but most important of all we recover the correct behaviour for large f AB-... 

Equilibrium geometries, dissociation energies, and energy separations between electronic states of different spin multiplicities are described substantially better by Mpller-Plesset theory to second or third order than by Hartree-Fock theory. 

In the following we shall consider the effect of polyconjugation and configuration of the polyene chain on the equilibrium dissociation of polyconjugated polyelectrolytes40, 41 45 264, such as PPA. The comparison of pAa and Z(energy of... 

Curves showing these two quantities as functions of rAB are given in Figure 42-2. It is seen that 1ps corresponds to attraction, with the formation of a stable molecule-ion, whereas pA corresponds to repulsion at all distances. There is rough agreement between observed properties of the hydrogen molecule-ion in its normal state and the values calculated in this simple way. The dissociation energy, calculated to be 1.77 v.e., is actually 2.78 v.e., and the equilibrium value of rAB, calculated as 1.32 A, is observed to be 1.06 A. 

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