Extreme undercooling (down to 90 K) of liquid metal nanoparticles

G. B. Parravicini (1) , A. Stella (1) , P. Ghigna (2) , G. Spinolo (2) , A. Migliori (3) , F. d'Acapito (4) , R. Kofman (5)

1 Dipartimento di Fisica A. Volta
2 Dipartimento di Chimica Fisica M. Rolla
3 LAMEL/CNR
4 GILDA-CRG
5 LPMC - Laboratoire de physique de la matière condensée

Low-melting-point metal nanoparticles show remarkable undercoolings: exceptional values DeltaT/Tm~=0.5 were previously reported for confined Ga droplets in the 100–1000 nm range. This was considered a characteristic limiting temperature for Ga. We here give evidence that Ga nanoparticles in the 3–15 nm range can be undercooled at least down to 90 K (DeltaT/Tm>=0.7) without crystallization. Since computations and experiments on clusters with <50 atoms show on the contrary the signatures of melting at temperatures well above the bulk value, the result is particularly relevant in stressing the importance of interfacial and finite-size effects on the thermodynamics of the nanoscale.

G. B. Parravicini, A. Stella, P. Ghigna, G. Spinolo, A. Migliori, et al.. Extreme undercooling (down to 90 K) of liquid metal nanoparticles. Applied Physics Letters, 2006, 89 (3), pp.033123. ⟨10.1063/1.2221395⟩. ⟨insu-00357951⟩