Experimental Determination of the Weiss Temperature of Mn12-Ac and Mn12-Ac-MeOHChemistry Faculty Publications
AbstractWe 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 lc and square cross section of side la. 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 Tc≈0.85 K and ≈0.74 K for Mn12-ac and Mn12-ac-MeOH, respectively. The difference in Tc 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.
Citation InformationChristos Lampropoulos, Shiqi Li, Lin Bo, Bo Wen, et al.. "Experimental Determination of the Weiss Temperature of Mn12-Ac and Mn12-Ac-MeOH" (2010)
Available at: http://works.bepress.com/christos_lampropoulos/1/