Transverse Relaxation in Canted Spin Structures

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]. 

Spin-canting is conveniently studied by Mossbauer spectroscopy with large magnetic fields applied parallel to the y-ray direction. The relative areas of the six lines are given by 3 p l l p 3, where 

In ferrites, the magnetization of the B-sublattice with octahedrally coordinated cations is usually parallel to the applied field whereas the magnetization of the /l-sublattice with tetrahedrally coordinated cations is in the opposite direction. 

in the case of fast relaxation between the two canted states the total average magnetic field, which is experienced by the nucleus, is given by [84, 85] 

In International Conference on the Applications of the Mossbauer Effect Proceedings, Science Academy, New Delhi, 1982, p. 91 

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