Experimental Determination of the Weiss Temperature of Mn12-Ac and Mn12-Ac-MeOH

Authors

Christos Lampropoulos, University of North FloridaFollow
Shiqi Li
Lin Bo
Bo Wen
M P. Sarachik
P Subedi
A D. Kent
Y Yeshurun
A J. Millis
S Mukherjee
G Christou

Document Type

Article

Publication Date

2010

Abstract

We report measurements of the susceptibility in the temperature range from 3.5 to 6.0 K of a series of Mn₁₂-ac and Mn₁₂-ac-MeOH samples in the shape of rectangular prisms of length l_c and square cross section of side l_a. The susceptibility obeys a Curie-Weiss law, χ=C/(T−θ), where θ varies systematically with sample aspect ratio. Using published demagnetization factors, we obtain θ for an infinitely long sample corresponding to intrinsic ordering temperatures T_c≈0.85 K and ≈0.74 K for Mn₁₂-ac and Mn₁₂-ac-MeOH, respectively. The difference in T_c for two materials that have nearly identical unit cell volumes and lattice constant ratios suggests that, in addition to dipolar interactions, there is a nondipolar (exchange) contribution to the Weiss temperature that differs in the two materials because of the difference in ligand molecules.

Comments

Originally published in Physical Review B, 82, 174405, 2010

http://dx.doi.org/10.1103/PhysRevB.82.174405

Recommended Citation

Lampropoulos, Christos; Li, Shiqi; Bo, Lin; Wen, Bo; Sarachik, M P.; Subedi, P; Kent, A D.; Yeshurun, Y; Millis, A J.; Mukherjee, S; and Christou, G, "Experimental Determination of the Weiss Temperature of Mn12-Ac and Mn12-Ac-MeOH" (2010). Chemistry Faculty Research and Scholarship. 10.
https://digitalcommons.unf.edu/achm_facpub/10