Pair Interaction Model Research Articles

Structure and phase transformation of an 84 layered rhombohedral polytypic crystal of cadmium iodide

Phase transformation studies on an eightyfour layered rhombohedral polytype of cadmium iodide are reported. The detailed atomic structure of the initial and transformed polytypes is determined and based on this, structural geometrical schemes embodying the transformation are put forward. Also the stacking fault energies of the structures are evaluated by the pair interaction and central force models. Evidence and arguments are advanced to show that the transformation of one polytype into another polytype takes place in such a way so as to lower the stacking fault energy of the polytype.

Evidence for a Strong Three-Body Force in the Triton

Publisher Summary This chapter explores the evidence for a strong three-body force in triton. The chapter utilizes the existing charge form factor data for 3He, 3H, and some assumptions to produce a model of the triton wave function compatible with the constraints. Given the wave function, the Schrodinger equation may be trivially solved for the effective local potential. The discrepancy between this potential and those predicted by pair-interaction models in the domain, where all three particles are close together, appears to provide clear evidence of a strong attractive three-body force., The chapter discusses an analysis for a broad band of possible 3H curves centered to eliminate the uncertainty introduced by extending the 3H curve. These studies indicate that the sum of all experimental uncertainties affecting the curves produces a net effect of most 4–5% in the results. The chapter discusses the structure of the model that is motivated by the results of numerous model calculations utilizing a hyperspherical basis.

Effects of Atomic Ordering on the Curie Temperature of Fe3Pt

The ferrromagnetic Curie temperatures were measured for ordered and disordered phases of Fe 1- x Pt x (0.25≤ x ≤0.30). The effect of atomic ordering on the Curie temperature was discussed by a pair-interaction model. It was concluded that Fe-Fe pair interaction is negative when only the nearest neighbor pair interactions were taken into account.

The thermoelectric power of dilute gold-iron alloys

We have measured the thermoelectric power of a number of Au-Fe alloys, with Fe concentrations between similar 10 and 1900 ppm. Measurements were made between 0.4 and 30 K in fields up to 70 kOe. The alloys exhibited the familar `giant' thermopower in zero field, the peak value observed being - 15 μ V K-1 at about 10 K. Both the order of magnitude and the temperature dependence of the zero-field thermopower agree fairly well with Kondo's theory of spin-flip scattering. The thermopower of all but the most dilute alloys shows an initial increase in a magnetic field, which we believe is caused by Fe-Fe interactions. The thermopower then decreases due to `freezing-out' of spin-flip scattering and a simple pair-interaction model accounts for most of this observed behaviour. For the most concentrated alloy the decrease is not observed, even for the maximum field applied. For still higher fields (and lower concentrations) the thermopower decreases approximately as 1/H, as is suggested by a recent perturbation calculation.

Thermotransport of substitutional impurities in copper

AbstractThermotransport of antimony, tin, indium, silver, cobalt, and nickel in copper is investigated in the temperature range between 950 and 1050 °C. The heats of transport were measured by the method of stationary redistribution of these elements in tracer amounts in a linear temperature gradient. The experimental results confirm both the intrinsic and electron interaction contribution to the heat of transport, theoretically anticipated for substitutional impurities in f.c.c. metals on the basis of a pair interaction model and Gerl's theory.

Pair interaction models for fine particle assemblies

Pair interaction models for fine particle assemblies

Note on the two-nucleon stripping reaction

The magnitude of the two-nucleon stripping reactions is calculated using the pairing interaction model. The calculation also is applied to final states of collective type. For some types of reaction a collective enhancement of the reaction cross section is predicted.

Symmetry of Configurational Entropy in Lattice Statistics

An investigation is made of the general conditions under which the configurational entropy of a binary solid solution is symmetrical with respect to composition about the 50–50 composition point. Spin coordinate and occupancy number representations of the configurational energy are discussed. When the sites of the site array are equivalent due to spatial symmetry, the configurational entropy is symmetrical for any pair interaction model. Asymmetry of the configurational entropy implies the presence of some n-site interactions, n=3, 5, 7, .... Application of these results to order-disorder alloy and physical adsorption systems is considered.