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Abstract Results are reported for Mn intercalated Zr 2 Te 2 P, where x-ray diffraction , energy dispersive spectroscopy, and transmission electron microscopy measurements reveal that the van der Waals bonded Te–Te layers are partially filled by Zr and Mn ions. This leads to the chemical formulas Zr 0.07 Zr 2 Te 2 P and Mn 0.06 Zr 0.03 Zr 2 Te 2 P for the parent and substituted compounds, respectively. The impact of the Mn ions is seen in the anisotropic magnetic susceptibility, where Curie–Weiss fits to the data indicate that the Mn ions are in the divalent state. Heat capacity and electrical transport measurements reveal metallic behavior, but the electronic coefficient of the heat capacity ( γ Mn ≈ 36.6 mJ (mol·K 2 ) −1 ) is enhanced by comparison to that of the parent compound. Magnetic ordering is seen at T M ≈ 4  K, where heat capacity measurements additionally show that the phase transition is broad, likely due to the disordered Mn distribution. This transition also strongly reduces the electronic scattering seen in the normalized electrical resistance. These results show that Mn substitution simultaneously introduces magnetic interactions and tunes the electronic state, which improves prospects for inducing novel behavior in Zr 2 Te 2 P and the broader family of ternary tetradymites. 

This paper describes and demonstrates an approach to improve the management of risks from small-probability events that can lead to large consequences. It applies a decision-based theory to account for limited information in estimating frequencies for rare events to large rockfill dam in Norway that is being assessed for rehabilitation. Uncertainties are considered specifically in estimating the overtopping hazard for the existing dam and for an elevated dam crest. Uncertainty in the estimates of the overtopping hazard curve means that smaller costs of dam failure and/or larger costs of rehabilitation may be justified. From a practical perspective, a cost of rehabilitation in this case that is nearly ten times larger could be justified when the uncertainty in the estimate of the hazard curve is considered. The value of perfect information about the hazard curve increases as the amount of information available decreases and as the cost of failure relative to the cost of rehabilitation decreases. In this case, the value of perfect information about the hazard curve is about 25 percent of the cost to raise the dam crest.