ISSN:
1434-6079
Keywords:
36.40.+d
;
65.40.−f
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract Specific-heat measurements on the cluster compound Au55(P(C6H5)3)12Cl6 at temperatures 0.06 K ≤T≤3 K and in magnetic fields 0≤B≤6 T are reported. While above 0.6 K the specific heatC is dominated by the inter-cluster vibrational contribution observed previously, an anomalous increase ofC towards lowT is observed below 0.3 K, withC ∼T −2. This contribution develops into a Schottky-like anomaly forB≥0.4 T, indicating that it might be attributed to local moments which are also observed in ESR measurements. From the height of the anomaly one can infer that approximately one tenth of the Au55 clusters carry a magnetic moment. For 0.6 K≤T≤1 K andB=0 our data indicate the absence of a linear electronic specific-heat contribution expected for bulk Au. This possibly constitutes the first direct observation of the quantum-size effect on electronic energy levels in the specific heat.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01544003