Abstract
We demonstrate that the short-range spin correlator , a fundamental measure of the interaction between adjacent spins, can be directly measured in certain insulating magnets. We present magnetostriction data for the insulating organic compound , and show that the magnetostriction as a function of field is proportional to the dominant short-range spin correlator. Furthermore, the constant of proportionality between the magnetostriction and the spin correlator gives information about the spin-lattice interaction. Combining these results with the measured Young’s modulus, we are able to extract , the dependence of the superexchange constant on the Ni interionic distance .
- Received 7 November 2007
DOI:https://doi.org/10.1103/PhysRevB.77.020404
©2008 American Physical Society