The low-temperature heat capacities of Tb, Lu and Y

The heat capacities of Tb, Lu and Y, refined by solid state electro-transport processing have been measured between 1.5 and 16K. Below 4K the results were fitted to the expression C= gamma T+AT3 where for Tb the nuclear and magnetic contributions were first calculated and subtracted from the total heat capacity. The resultant values of gamma (mJ mol-1K-2) and limiting Debye temperatures theta D(T to 0) were as follows. Tb: gamma =4.4+or-0.1, theta D=178+or-2K; Lu: gamma =6.8+or-0.1, theta D=205+or-3K; Y: gamma =8.2+or-0.1, theta D=248+or-3K. The Debye temperature was found in all instances to decrease by about 10% between 4 and 16K.