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All rights reservedNo part of this publication may be reproduced in any form without written permission from the publisher PREFACE TO THE AMERICAN EDITIONThe principal reasons which induced the authors to write this book and the features of the book are set forth in the preface to the Russian edition.That section of the science of metals which in Russian is called "metallovedenie" or the "physical chemistry of metals" is generally referred to in scientific and technical literature published in the English language by the term "physical metallurgy." These concepts are much broader than the term" metallography," used in the scientific and technical literature of various countries, and applied solely to research on the interrelationships of the structure and properties of metals and alloys.Each science must have its own subject and its own method of research. Certainly, all specialists will agree that metals and alloys, including their solid solutions, mechanical mixtures, and metallic compounds, form the subject of "physical metallurgy" or "physical chemistry of metals." The aim of this science. is to produce a theory and to elucidate the experimental relationships which ought finally to make it possible to calculate quantitatively alloys Of given properties for any working conditions and parameters.With regard to the methods of research on metals and alloys, we assume that "physical metallurgy" may properly employ any theoretical and experimental methods which will help to solve its basic problems. The experience of the last few decades has shown that among the experimental methods a leading position is occupied by the physicochemical analysis of metal systems developed by N. S. Kurnakov, that is to say, the systematic investigation of the phYSical properties of alloys as a function of he variation of their chemical composition and phase composition. This method has also been employed for investigating the interrelationship of the structure and properties of alloys at different temperatures and pressures (see E. M. Savitsky, The Influence of Temperature on the Mechanical Properties of Metals and Alloys, Stanford University Press, 1961). The "physical chemistry of metals" makes extensive use of physicochemical analysis. The science of metals and alloys absorbs all the achievements of the exact fundamental sciences, primarily physics and chemistry. It may even be said more precisely:The "physical chemistry of metals" or "physical metallurgy" is the synthesis of the physics of metals and the chemistry of metal alloys. The distribution and energy of electrons is the basic factor determining the crystal structure and all the properties of metals and alloys. The main problems which have to be solved in the framework of these sciences are the following: the electronic structure and nature of the interatomic bond in metal crystals, solid solutions of metals and metallic compounds, the development of methods for the quantitative measurement of the value of the interatomic forces with variation in the fundamental parameters...

Precision measurements of the Hall effect have been carried out for both archetypal heavy fermion compound -CeCu 6 and exemplary solid solutions CeCu 6-x Au x (x= 0.1 and 0.2) with quantum critical behavior. The experimental results have been obtained by technique with a sample rotation in magnetic field in the temperature range 1.8-300K. The experiment revealed a complex activation type dependence of the Hall coefficient R H (T) in CeCu 6 with activation energies E a1 /k B ≈ 110K and E a2 /k B ≈ 1.5K in temperature ranges 50÷300K and 3÷10K, respectively. Microscopic parameters of charge carriers transport (effective masses, relaxation time) and localization radii a p1,2 * of heavy fermions (a p1 *(T>50K)~ 1.7 Å and a p2 *(T<20K)~ 14 Å) were estimated for CeCu 6 . The second angular harmonic contribution has been established in the Hall voltage of CeCu 5.9 Au 0.1 and CeCu 6 at temperatures below T*~24K. A hyperbolic type divergence of the second harmonic term in Hall effect R H2 (T)≈ C(1/T-1/T*) at low temperatures is found to be accompanied with a power-law behavior R H (T)~ T -0.4 of the main contribution in the Hall coefficient for CeCu 5.9 Au 0.1 compound with quantum critical behavior. PACS: 72.15.Qm. 1. During last decade it was demonstrated perfectly [1-7] that CeCu 6-x Au x solid solutions are in the number of the most convenient and interesting examples of the systems with non-Fermi-liquid behavior in the vicinity of antiferromagnetic quantum critical point (QCP). Among the CeCu 6-x Au x family the CeCu 6 is the canonical heavy fermion (HF) intermetallic compound with an enhanced Pauli magnetic susceptibility and a huge value of the low temperature electronic specific heat coefficient γ = 1.53 J/(mole K 2 ) [8]. These features place this compound together with CeAl 3 [9] as the heaviest of all known HF systems. Alloyingwith Au induces the long-range antiferromagnetic order above QCP at x c ≈ 0.1 with the Neel temperature that increases linearly in the 0.1< x≤ 1 range and reaches T N ≈2.3K for CeCu 5 Au [10]. Understanding the behavior of this kind of systems close to antiferromagnetic QCP is a current area of active research. In this field, the main question is the mechanism by which the mass of heavy electrons diverges in the approach to the antiferromagnetic instability [11].According to the comments proposed in [11], Hall coefficient is the one of the most promising but, surprisingly, untested probes of the quasiparticles involved in the conduction process on both the paramagnetic and antiferromagnetic sides of the QCP. From the point of view of [11], the Hall coefficient variation through the quantum phase transition (QPT) can be considered as a key experiment to choose between different scenario of QPT and to test the mechanism by which the Fermi surface transforms between the paramagnet and antiferromagnet.Up to now the Hall effect measurements of CeCu 6 [12][13][14][15] and the exemplary solid solutions CeCu 6-x Au x [16][17] have been produced by ordinary ac-(or dc-) four probe method where the H...

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