Magnetic moment quantities

Neutron magnetic moment Partial molar quantity A... 

Much of the Pt Mossbauer work performed so far has been devoted to studies of platinum metal and alloys in regard to nuclear properties (magnetic moments and lifetimes) of the excited Mossbauer states of Pt, lattice dynamics, electron density, and internal magnetic field at the nuclei of Pt atoms placed in various magnetic hosts. The observed changes in the latter two quantities, li/ (o)P and within a series of platinum alloys are particularly informative about the conduction electron delocalization and polarization. 

Neutron magnetic moment Ahsr Partial molar quantity X... 

Three basic equations (3.10-3.12) are needed to describe the technique. In the equations, p is the magnetic moment of the electron, sometimes also written as pe, g is called the g factor or spectroscopic splitting factor, S is defined as the total spin associated with the electron (in bold type because it is considered as a vector), B is the imposed external magnetic field (also defined as a vector quantity), and... 

The angular momentum L has associated with it a magnetic moment /z. Both are vector quantities and they are proportional to each other. The proportionality factor y is a constant for each nuclide (i.e. each isotope of each element) and is called the gyromagnetic ratio, or sometimes the magnetogyric ratio. The detection sensitivity of a nuclide in the NMR experiment depends on y nuclides with a large value of y are said to be sensitive (i.e. easy to observe), while those with a small y are said to be insensitive. 

In the previous section several equations were described that can be used to calculate MCD spectra. If the spectra are to be calculated using the transition-based approach described in Sections II.A.1-II.A.4, a number of quantities must be evaluated. These include the perturbed and unperturbed excitation energies, the perturbed and unperturbed transition moments between the ground and excited states, and/or the magnetic moment of the ground state. If an MCD spectrum is to be calculated with the imaginary Verdet approach described in Section II.A.6, then the first-order correction to the frequency-dependent polarizability due to a magnetic field is required. 

Analogous quantities to die electric moments can be defined when the external perturbation takes the form of a magnetic field. In this instance die first derivative defines the permanent magnetic moment (always zero for non-degenerate electronic states), the second derivative the magnetizability or magnetic susceptibility, etc. 

The quantity gNI is commonly called the nuclear magnetic moment and is listed as such in tables actually, gNI is not the magnitude of ftN, but rather is the maximum z component of nN in units of nuclear magnetons. 

Remark. We assumed that Y(t) is a Markov process. Usually, however, one is interested in materials in which a memory effect is present, because that provides more information about the microscopic magnetic moments and their interaction. In that case the above results are still formally correct, but the following qualification must be borne in mind. It is still true that p y0) is the distribution of Y at the time t0, at which the small field B is switched off. However, it is no longer true that this p(y0) uniquely specifies a subensemble and thereby the future of Y(t). It is now essential to know that the system has aged in the presence of B + AB, so that its density in phase space is canonical, not only with respect to Y, but also with respect to all other quantities that determine the future. Hence the formulas cannot be applied to time-dependent fields B(t) unless the variation is so slow that the system is able to maintain at all times the equilibrium distribution corresponding to the instantaneous B(t). 

The theory of the magnetic susceptibility of nickel(II) complexes is well established and several review articles have already appeared.375-379 A quantity of interest in studying the magnetic properties of nickel(II) complexes is the effective magnetic moment p = (8xT). 

It is convenient for many purposes to have a quantity which summarizes magnetic properties and which is, ideally at least, independent of temperature. We define the magnetic moment , in units of the Bohr magneton ... 

Electron Spin. One of die properties of electrons that became evident during die study of optical spectra of atoms was that of electron spin. The suggestion was made by Uhlenbeck and Goudsmit in 1925 that one of die features of such spectra could be understood if each electron had associated with it a quantity called spin, which is similar in many ways to angular momentum. Each electron also has a certain magnetic moment which affects the energy in the presence of a magnetic field.2 This property also has been incorporated into the wave concepts of quantum mechanics. 

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