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Morse modified

It is difficult to point to the basic reason why the average-potential model is not better applicable to metallic solutions. Shimoji60 believes that a Lennard-Jones 6-12 potential is not adequate for metals and that a Morse potential would give better results when incorporated in the same kind of model. On the other hand, it is possible that the main trouble is that metal solutions do not obey a theorem of corresponding states. More specifically, the interaction eAB(r) may not be expressible by the same function as for the pure components because the solute is so strongly modified by the solvent. This point of view is supported by considerations of the electronic models of metal solutions.46 The idea that the solvent strongly modifies the solute metal is reached also through a consideration of the quasi-chemical theory applied to dilute solutions. This is the topic that we consider next. [Pg.137]

The attractive energies 4D(cr/r)6 and ae2/2 r4 have two important effects on the vibrational energy transfer (a) they speed up the approaching collision partners so that the kinetic energy of the relative motion is increased, and (b) they modify the slope of the repulsive part of the interaction potential on which the transition probability depends. By letting m °°, we have completely ignored the second effect while we have over-emphasized the first. Note that Equation 12 is identical to an expression we could obtain when the interaction potential is assumed as U(r) = A [exp (— r/a)] — (ae2/2aA) — D. Similarly, if we assume a modified Morse potential of the form... [Pg.64]

Verwey and Hamaker (10) have modified the Morse curve to take into account the approach of two charged bodies, as shown in Figure 4. Here, as one moves outward toward increasing distance of separation, an electrostatic repulsion is encountered because the charges are similar. A secondary minimum is then encountered as a result of the concentration of counter ions around each charged particle. The shallowness of the secondary minimum shows that the deflocculated system is metastable. The importance of the Verwey and Hamaker concept lies in its ability to show graphically the correlation between the secondary minimum and the metastable position. A, Figure 1. [Pg.97]

This specific problem was addressed by Burgi and Dunitz (1987), using a Morse function modified to treat fractional bonds. The observed ground state structure of a given molecular fragment, e.g. the O-C-O fragment of the acetals [96], was then treated as a distorted version of a standard structure of known molecular dimensions. Using experimental values of the... [Pg.175]

Molecular emissions are due to electronic transitions within the molecule but are modified by variations in bond length. The bond between two atoms assumes a particular length as a result of the various forces acting upon the atoms involved. The attractive forces between the electrons of one atom and the nucleus of the other atom are balanced by the repulsive forces of the like-charges carried by both nuclei. The Morse curve (Figure 2.10) describes... [Pg.46]

For comparison with our results in table 3, which presents values of 20 adjusted parameters with 15 parameters constrained to define the rotational g factor, Dulick et alii [115] required also 20 adjusted parameters, with a constrained parameter T> for the equilibrium binding energy for a function of potential energy having a modified Morse form. The latter parameter is specified as... [Pg.295]

A postulated advantage of accurate prediction of wave numbers of transitions far above the measured range through representing potential energy in a modified Morse form is plainly illusory. [Pg.296]

The above data have been analyzed theoretically within the same model as described for the chemical shift tensor (5iso In order to understand the chemical shift observed within the KDP family, we concentrate here on the polarizability modified double-well potential of the protons, which has been modelled by two back-to-back Morse potentials (see Chap. 1 in this volume). The separation between the protons and the centre of the left (/) or right (r) PO4 shell... [Pg.42]

Table 4.5). The first was the three-dimensional procedure of Hartley (ref. 332) which employs the following three solvents 1) 1.5% (v/v) formic acid 2) benzene-acetic acid (9 1, v/v) 3) ethyl acetate-methanol-acetic acid (20 1 1, by vol.). The second method was the one-dimensional procedure of Morse and Horecker (ref. 333) and employed a modified solvent system containing benzene-pyridine-acetic acid (80 20 2) with 25 pi 2-mercaptoethanol added per 50 ml of solvent. [Pg.74]

Bennett, R., U. Kambhampati, S. Morse, Y. Ismael. 2006. Farm level economic performance of genetically modified cotton in Maharashtra, India. Review of Agricultural Economics 28 59-71. [Pg.184]

More recently, Yates and Lester230 fitted Liu s surface with a slightly modified form of the Porter-Karplus formulas after first fitting Liu s H2 potential to a simple Morse function. They then use the resulting surface to calculate the three-dimensional classical trajectory of the system. Their empirical fit very closely duplicates Liu s saddle-point properties. Reaction probabilities on this surface are compared with those on the PK surface. [Pg.54]

As an illustration of the procedure a set of modified Morse curves to describe C-N bonds of different order is shown in figure 8. The internuclear... [Pg.163]

Use Mathcad or some other symbolic algebra program to solve the Ai secular determinant of Table 41-2 in a manner similar to that shown in Fig. 5 for the Bi determinant. Modify the Mathematica commands shown in Fig. 6 to see the square of the I2 harmonic oscillator and Morse wavefunctions and their overlap product for v" = 2 and v = 0, 5, 10, 15, 20, and 25. Obtain plots of these results and discuss the trends that you see. Repeat the exercise for v = 40 and v" = 0, 1, 2, 3, 4, and 5 and note the dramatic intensity variations for the Morse oscillator. Emission from this state, which can be populated by the 520.8-nm krypton ion laser line, is strong to even v" levels but is very weak to odd v" levels (up to about v" = 30). [Pg.89]

The author examines with success the efficiency of the methods by their applications to bound states for the one-dimensional harmonic oscillator, anharmonic oscillators, the Morse potential, and the modified Poschl-Teller potential in quantum mechanics. [Pg.399]

The authors in this paper present an explicit symplectic method for the numerical solution of the Schrodinger equation. A modified symplectic integrator with the trigonometrically fitted property which is based on this method is also produced. Our new methods are tested on the computation of the eigenvalues of the one-dimensional harmonic oscillator, the doubly anharmonic oscillator and the Morse potential. [Pg.400]

Electronic levels and vibrational constants are based on the review of Rosen (1 ) as modified by the additional data of Novikov and Gurvich (7 ). Vibrational constants are adjusted for natural isotopic abundances. B is calculated from r which is estimated by comparison of the bond lengths of MX2(M-Mg, Ca, Sr, Ba and X=F, Cl) with those of MgCl, CaCl and MF(M Mg, Ca, Sr, Ba). The value of is estimated from the Morse potential function. [Pg.786]

To study reactions, in which bonds are broken or formed, it is evident that the analytical form of the bond energy function in equation 16 is inappropriate. It can be modified by including terms, such as Morse functions, that permit bond dissociation, although no work appears to have been performed to introduce such terms into a MM potential function for reacting systems in a systematic way. [Pg.138]

Figure 2.4 Classification of negative-ion Morse potential energy curves originally presented by Herschbach in 1966. The curves are calculated from actual data. The empty spaces are impossible combinations. These classifications have been modified so that they are symmetrical and all combinations are possible [34, 36]. Figure 2.4 Classification of negative-ion Morse potential energy curves originally presented by Herschbach in 1966. The curves are calculated from actual data. The empty spaces are impossible combinations. These classifications have been modified so that they are symmetrical and all combinations are possible [34, 36].

See other pages where Morse modified is mentioned: [Pg.49]    [Pg.60]    [Pg.538]    [Pg.224]    [Pg.224]    [Pg.102]    [Pg.300]    [Pg.311]    [Pg.286]    [Pg.296]    [Pg.137]    [Pg.151]    [Pg.223]    [Pg.187]    [Pg.132]    [Pg.49]    [Pg.65]    [Pg.85]    [Pg.258]    [Pg.107]    [Pg.181]    [Pg.81]    [Pg.422]    [Pg.181]    [Pg.32]    [Pg.552]    [Pg.49]    [Pg.383]    [Pg.425]    [Pg.428]    [Pg.41]   
See also in sourсe #XX -- [ Pg.198 ]




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