Specific Heat of Gadolinium and Ytterbium Metals between 0.4 and 4°K

摘要: The heat capacities of gadolinium and ytterbium metals are measured between 0.4 4 deg K in a He/sup 3/ cryostat. For gadolinium, anomalous humps observed C/sub p/ at 1.1, 1.6, 3.7 K. ground state the Gd/ sup 3+/ ion is S/sup 8//sub 7/2/ an d consequently, as result zero orbital angular momentum 4f electrons, nuclear specific small. much larger than expected for metal alone; excess entropy could be attributed to magnetic ordering Gd/sup ions Gd/sub 2/O/sub impurity (0.54% oxygen our sample). ytterbium, K, can expressed by p/(mj/mole K) = 1.180T/sup + 2.90T 0.012T/sup -2/. lattice corresponds Debye THETA 118.1 which considerably lower value approximates 160 other higher rare earths. electronic C /sub E/ also smaller usual 10T. In nonmagnetic 5d electron, normallymore » conduction band, added shell thereby becomes hill. This explains differences small term proportional T/ -2/, probably caused long-range exchange-type coupling moments rare-earth impurities sample. (auth)« less