Lippincott-Schroeder potential

Vener, M. V., How reliable is the Lippincott-Schroeder potential for the OH"N hydrogen bonded fragment in the gas phase , Chem. Phys. Lett. 244, 89-92 (1995). 

In a different approach it should be possible to characterize the acid strength of OH groups according to their dissociation energies Do, which are obtained from combined fundamental and overtone spectroscopic studies, applying the Morse or the Lippincott-Schroeder potential functions [40,41]. But as has been pointed out. Do of the free hydroxyls is no measure for its acidity, moreover it forms the basis for the changes of the shape of the potential curves occurring upon interaction with a proton acceptor. 

Figure 13.12 Relation between the H-bond lengths and strengths involving oxygen acids and bases. The circles are classical potential energies from ab initio calculations, the squares are experimental H-bond enthalpies and the line is the relation given by the Lippincott-Schroeder potential described in Appendix V.

The Reid potential function [175] is derived by the Lippincott-Schroeder one, with the aim of a better description of the O-H- O bonds and takes into account also the OH and O O stretching motions. 

Fig. 2.7. The effective interaction potential between two oxygen atoms joined by a hydrogen hond O-H... O as calculated from the model of Lippincott Schroeder (1955).

Scott andScheraga (1966c) and Ooi etal. (1967) have used a form of the potential function of Lippincott and Schroeder (1955) and Schroeder and Lippincott (1957), modified to take account of the angular dependence (Moulton and Kromhout, 1956). The form used by Ooi etal. (1967) is... 

Lippincott, E. R., and R. Schroeder General Relation between Potential Energy and Internuclear Distance. II. Polyatomic Molecules. J. Amer. chem. Soc. 78, 5171-5178 (1956). 

Schroeder R, Lippincott ER (1957) Potential function model of the hydrogen bond. II. J Phys Chem 61 921-928... 

Empirical Potential Functions. There is one more type of treatment which is properly classified as an empirical model of the H bond. An explicit form is assumed for the potential function associated with the movement of the H atom within the H bond. Nordman and Lipscomb have proposed such a model based upon a Morse function (1521). This proposal will not be explored, however, in favor of the similar and more completely developed potential Junction model of Lippincott and Schroeder (1242, 1815). The potential function is written as a sum of four terms, the first of which has the form... 

The potential function contains, in addition to the spatial variables r and R, ten parametric variables. All but three of these are related to observational data, with the aid of such relations as (dV/dr)equiUb. = 0. With the two assumptions that r = r and k, = ko, only one parameter remains and that one is selected to obtain optimum fit to certain data. Lippincott and Schroeder have used this potentiail function in attempting to correlate such experimental behavior as the dependence of frequency shift, Av on R, of A , on H bond energy, and of r on R. 

In this model the ionization step is pictured as a tunneling of jmto-tons between two potential energy minima symmetrically located. Conway and co-workers used the Morse equation, adthough Lippincott and Schroeder s might be more suitable (see Section 8.2.5). 

E. R. Lippincott and R. Schroeder. J. Chem. Phys. 23, 1131-41 (1955). Theory potential energy-distance relation. 

R. Schroeder and E. R. Lippincott. J. Phys. Chem. 61, 921-8 (1957). Theory potential function model for H bonds. 

Ehb is a hydrogen bond energy term, modified from the definition of Schroeder and Lippincott (]J), to be a function with one potential parameter. 

Lippincott, E. R., Finch, J. N. Schroeder, R. (1959). Potential function model of hydrogen bond systems. In Hydrogen Bonding (ed. D. Hadzi), pp. 361—74. London Pergamon Press. [43]... 

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