| 23 |
|
droplets. |
| 24 |
|
|
| 25 |
|
Much of the experimental work on this subject has been carried out in |
| 26 |
< |
the Hartland and von~Plessen |
| 27 |
< |
groups.\cite{HartlandG.V._jp0276092,Hodak:2000rb,Hartland:2003lr,HuM._jp020581+,Petrova:2007qy,plech:195423} |
| 28 |
< |
They have [BRIEF SURVEY OF THE EXPERIMENTAL WORK] |
| 26 |
> |
the Hartland and von~Plessen groups.\cite{HartlandG.V._jp0276092,Hodak:2000rb,Hartland:2003lr,Petrova:2007qy,Link:2000lr} These experiments mostly use the technique of time-resolved optical pump-probe spectroscopy where a pump laser pulse serves to excite conduction band electrons in the nanoparticle and a following probe laser pulse allows the electron-phonon coupling to be observed as a function of time. Hu and Hartland have observed a direct relation between the size of the nanoparticle and the observed cooling rate using such pump-probe techniques.\cite{HuM._jp020581+} Pleach {\it et al.} have use pulsed x-ray scattering as a probe to directly access changes to atomic structure following pump excitation.\cite{plech:195423} They further determined that heat transfer in nanoparticles to the surrounding solvent is goverened by interfacial dynamics and not the thermal transport properties of the solvent. |
| 27 |
|
|
| 28 |
|
|
| 29 |
|
Since these experiments are often carried out in condensed phase |
| 94 |
|
resonance (SPR) of bimetallic core-shell structures typically show two |
| 95 |
|
distinct resonance peaks where mixed particles show a single shifted |
| 96 |
|
and broadened resonance.\cite{Hodak:2000rb} The SPR for pure silver |
| 97 |
< |
occurs at 400 nm and for copper at 570 nm. On Al$_2$O$_3$ films, |
| 98 |
< |
these resonances move to 424 nm and 572 nm for the pure metals. For |
| 97 |
> |
occurs at 400 nm and for copper at 570 nm.\cite{HengleinA._jp992950g} |
| 98 |
> |
On Al$_2$O$_3$ films, these resonances move to 424 nm and 572 nm for the pure metals. For |
| 99 |
|
bimetallic nanoparticles with 40\% Ag an absorption peak is seen |
| 100 |
|
between 400-550 nm. With increasing Ag content, the SPR shifts |
| 101 |
|
towards the blue, with the peaks nearly coincident at a composition of |
| 102 |
< |
57\% Ag. The authors (WHO?) cited the existence of a single broad |
| 102 |
> |
57\% Ag. Gonzalo {\it et al.} cited the existence of a single broad |
| 103 |
|
resonance peak as evidence of a mixed alloy particle rather than a |
| 104 |
|
phase segregated system. Unfortunately, they were unable to determine |
| 105 |
|
whether the mixed nanoparticles were an amorphous phase or a |
