Structure spinning

Defects in ferrimagnetic structures often lead to noncollinear (canted) spin structures. For example, a diamagnetic substitution or a cation vacancy can result in magnetic frustration which leads to spin-canting such that a spin may form an angle 6c with the collinear spins in the sample [80, 81]. Similarly, the reduced number of neighbor ions at the surface can also lead to spin-canting [80-83]. 

An interesting study of oxidic spinel ferrites of the type CO cNi5/3 xFeSbi/304 was reported [21], where three different Mbssbauer-active probes Fe, Ni and Sb were employed on the same material. The results have been interpreted in terms of the cation distributions over spinel A- and B-lattice sites, magnetic moments and spin structure, and the magnitude of the supertransferred hyperfine... 

MnAs exhibits this behavior. It has the NiAs structure at temperatures exceeding 125 °C. When cooled, a second-order phase transition takes place at 125 °C, resulting in the MnP type (cf. Fig. 18.4, p. 218). This is a normal behavior, as shown by many other substances. Unusual, however, is the reappearance of the higher symmetrical NiAs structure at lower temperatures after a second phase transition has taken place at 45 °C. This second transformation is of first order, with a discontinuous volume change AV and with enthalpy of transformation AH. In addition, a reorientation of the electronic spins occurs from a low-spin to a high-spin state. The high-spin structure (< 45°C) is ferromagnetic,... 

D. R. Alcoba and C. Valdemoro, Spin structure and properties of the correlation matrices corresponding to pure spin states controlling the S-representability of these matrices. Int. J. Quantum Chem. 102, 629 (2005). 

The spin structure enhances computational efficiency since each of the blocks may be purified separately. 

Spin Structure and Properties of the Pure Two-Body Correlation Matrices in the Singlet State... 

Piris and Otto (PO) achieved a reconstruction functional D[ D] satisfying the most general properties of the 2-RDM [58]. They kept the spin structure from Refs. [52, 53], but introduced a new spatial dependence in the correction term of the 2-RDM. Calculated values for polarizabilities [59], ionization energies, equilibrium geometries, and vibrational frequencies [60] in molecules were... 

The spin structures of hematite are shown in Figure 6.8. Above Tm, the Fe ions are antiferromagnetically coupled across the shared octahedral faces along the c-axis. 

Fe402 core, spin structure, 43 310 [FejOfOAcljtpbnlj, structure, 43 310-311 (Fe2O(O5P(OC4H,))2(Me,[9]aneN,)2]2 40 376-yii... 

Miyagawa K, Kawamoto K, Nakazawa Y, Kanoda K (1995) Antiferromagnetic ordering and spin structure in the organic conductor, k-(BEDT-TTF)2Cu[N(CN)2]C1. Phys Rev Lett 75 1174-1177... 

Fig. 2. Relative energy differences between the spin states of [Fe2] 1, for each spin state optimized structures denoted opt as well as for single-point calculations on the optimized high-spin structure denoted as single point, where the energy of the closed-shell spin restricted state has arbitrarily been set to zero.

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