Since exceeding the Debye temperature of nickel appears to be necessary to produce heat from Ni-H systems, I was wondering if the Debye temperature of palladium must be exceeded too in Pd systems. I did a search for the Debye of temperature of palladium and found this abstract from 1966:
http://prola.aps.org/abstract/PR/v146/i2/p463_1 C. A. Mackliet<http://publish.aps.org/search/field/author/C.%20A.%20Mackliet>and A. I. Schindler<http://publish.aps.org/search/field/author/A.%20I.%20Schindler> U. S. Naval Research Laboratory, Washington, D. C. Received 31 January 1966; published in the issue dated June 1966 Specific-heat measurements in the 1.2 to 4.2°K range have been carried out on four H-Pd specimens having H/Pd atomic ratios of 0.57, 0.70, 0.81, and 0.88. Corresponding values of γ (the electronic-specific-heat coefficient) are 2.52, 1.38, 1.40, and 1.61 mJ/deg2 per g atom of palladium; values of ΘD(the Debye temperature) are 282, 273, 276, and 267°K, respectively. A "dynamic" method of measurement was necessarily employed because of the occurrence of an exothermic process in these alloys. The interpretation of the data was complicated by the interstitial character of these alloys, but the present results for the electronic specific heat appear to offer unusually direct support for the usual simple band picture of Pd and H-Pd alloys. Special care must be exercised in the interpretation of the Debye temperatures in this case. What is the "exothermic process in these alloys". Is it an anomalous heat effect or expected chemical effect? Anyway you can see that the Debye temperature of Pd is much lower than Nickel so it doesn't doesn't require any prewarming if it is at room temperature. harry Harry
