Magnetic contribution

It is clear that nonconfigurational factors are of great importance in the formation of solid and liquid metal solutions. Leaving aside the problem of magnetic contributions, the vibrational contributions are not understood in such a way that they may be embodied in a statistical treatment of metallic solutions. It would be helpful to have measurements both of ACP and A a. (where a is the thermal expansion coefficient) for the solution process as a function of temperature in order to have an idea of the relative importance of changes in the harmonic and the anharmonic terms in the potential energy of the lattice. 

Figure 4.7 Temperature dependence of the contribution to the total specific heat, reveals magnetization in 5 0e applied field of a pow- two distinct phase transitions. (Redrawn der sample of Gd(hfac)3NIT-Et n evidencing from Ref. [53] with data kindly provided by a phase transition around 1.8K. In the inset A. Lascialfari. (Published by American the magnetic contribution to the specific physical society).) heat, evaluated by subtracting the lattice...

Figure 9.7 Upper graph (a) showing zero zero field magnetic entropy for the same, field magnetic contribution to the heat (Taken from Ref. [26] with permission from...

From formula (3.21), we see that the temperature at which the maximum of the magnetic contribution to the specific heat occurs is determined by the energy splitting AE of the levels ... 

An example of magnetic contributions to the specific heat is reported in Fig. 3.9 that shows the specific heat of FeCl24H20, drawn from data of ref. [35,36]. Here the Schottky anomaly, having its maximum at 3K, could be clearly resolved from the lattice specific heat as well as from the sharp peak at 1K, which is due to a transition to antiferromagnetic order (lambda peak). 

We next include the magnetic contributions to the nonlinearity and the results are given in Table 9.6. 

It is noteworthy that the value of g is different from zero and relatively large. This result suggests that the electric and magnetic contributions to the nonlinearity are essentially of the same order of magnitude. This large value of the magnetic contributions is probably due to the near centrosym-metric arrangement of the monomer units in the helical polymer structure... 

However, the components of the yj2) e, e tensor are chiral (i.e., only present in a chiral isotropic medium), whereas the components of the tensors y 2) and y(2) meeare achiral (i.e., present in any isotropic medium, chiral or achiral). Hence, only the electric dipole response of chiral isotropic materials is related to chirality. The experimental work on chiral polymers described in Section 4 showed that large magnetic contributions to the nonlinearity are due to chirality. However, such contributions will therefore not survive in chiral isotropic media. In this respect, the electric dipole contributions associated with chirality may prove more interesting for applications. 

The study of chiral materials with nonlinear optical properties might lead to new insights to design completely new materials for applications in the field of nonlinear optics and photonics. For example, we showed that chiral supramolecular organization can significantly enhance the second-order nonlinear optical response of materials and that magnetic contributions to the nonlinearity can further optimize the second-order nonlinearity. Again, a clear relationship between molecular structure, chirality, and nonlinearity is needed to fully exploit the properties of chiral materials in nonlinear optics. 

Magnetic contributions to the Gibbs energy due to an internal magnetic field are present in all magnetically ordered materials. An additional energetic contribution... 

With decreasing particle size, the magnetic contributions from the surface will eventually become more important than those from the bulk of the particle, and hence surface anisotropy energy will dominate over the magnetocrystalline anisotropy and magnetostatic energies. A uniaxial anisotropy energy proportional to the particle surface S... 

Fig. 12. Magnetic contribution to the electrical resistivity of UAI2 as a function of the temperature (logarithmic scale)...

Curium metal is antiferromagnetic and its resistivity has been measured as well as that of isostructural non magnetic americium metal The resistivity difference is taken as the magnetic contribution and is shown in Fig. 13. It passes through a maximum for... 

As can be seen in fig. 47 the temperature dependence of the specific heat C(T) of TmNi2B2C shows pronounced anomalies at the critical temperature Tc as well as the magnetic ordering temperature Tn, which is different from the behaviour of HoNi2B2C where the magnetic contribution to C(T) dominates (fig. 38). 

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