Gold thermodynamic properties

Chui, Y.H., Grodiola, G., Snook, l.K. and Russo, S.P. (2007) Molecular dynamics investigation of the structural and thermodynamic properties of gold nanodusters of different morphologies. Physical Review B - Condensed Matter, 75, 033404-1-033404-4. 

White, J.L., Ore, R.L. and Hultgrev. R. (1957) The thermodynamic properties of silver-gold alloys. Acta Metallurgica, 5, 747-760. 

ICTFD A I DATA 0UTPUT 0P thermodynamic properties of gold... 

Decanolc acid was purchased from Aldrich Chemicals, Gold Label, and from BDH, special pure grade. BE was obtained from Shefford Chemicals. It was distilled and kept over molecular sieves. The preparation of NaDec and Its purification are the same as In previous studies (16). The purity of NaDec was checked by surface tension. A minimum In surface tension Is observed which disappears when NaDec Is prepared at a pH higher than 11. This suggests that the Impurity In NaDec Is most probably free decanolc acid. In consideration of the previous discussion (16), NaDec was prepared at a pH of 9.2 and used as such, since a trace of decanolc acid should have less effect on the thermodynamic properties than an excess of NaOH. 

Although one of the more complex electrochemical techniques [1], cyclic voltammetry is very frequently used because it offers a wealth of experimental information and insights into both the kinetic and thermodynamic details of many chemical systems [2], Excellent review articles [3] and textbooks partially [4] or entirely [2, 5] dedicated to the fundamental aspects and apphcations of cyclic voltammetry have appeared. Because of significant advances in the theoretical understanding of the technique today, even complex chemical systems such as electrodes modified with film or particulate deposits may be studied quantitatively by cyclic voltammetry. In early electrochemical work, measurements were usually undertaken under equilibrium conditions (potentiometry) [6] where extremely accurate measurements of thermodynamic properties are possible. However, it was soon realised that the time dependence of signals can provide useful kinetic data [7]. Many early voltammet-ric studies were conducted on solid electrodes made from metals such as gold or platinum. However, the complexity of the chemical processes at the interface between solid metals and aqueous electrolytes inhibited the rapid development of novel transient methods. 

Puliti, G., S. Paolucci, and M. Sen. 2011. Thermodynamic properties of gold-water nanolayer mixtures using molecular dynamics. Journal of Nanoparticle Research. 13,4277. 

The HT voltammetry with gold electrodes was also recently used to measure the surface partitioning constant of a soluble, redox-active surfactant at the air/water interface [25]. Malec and coworkers modified the surface of gold electrodes by self-assembly of short alkane chain thiols in order to mimic the thermodynamic properties of the air/water interface. They relied on the fact that the surface tensions of the air/water interface and of the liquid alkane/water interface are similar [8]. Indeed, the HT measurements of the Gibbs monolayer formation constant were in agreement with their surface tensiometry and Brewster angle microscopic measurements [25]. 

Furukawa et have presented a critical analysis of the thermodynamic properties of copper, silver, and gold from 0 to 300 K. 

G. T. Furukawa, W. G. Saba, and M. L. Reilly, Critical Analysis of the Heat-capacity Data of the Literature and Evaluation of Thermodynamic Properties of Copper, Silver and Gold from 0 to 300 K , National Bureau of Standards Reference Data Series NSRDS-NBS 181. 

Chui et studied the thermodynamic properties of larger gold clusters with roughly 1000 — 10000 atoms. Due to the size of the system they used the embedded-atom method. As mentioned above, this method may suffer from some inaccuracies for smaller clusters, but for the systems of the study of Chui et al. it may be more accurate. In order to include temperature effects they considered Gibbs free energy,... 

Much has been written about solid metal electrodes, which have now largely displaced liquid mercury. Those most often used as redox ( inert ) electrodes for studying electron transfer kinetics and mechanism, and determining thermodynamic parameters are platinum, gold, and silver. However, it should be remembered that their inertness is relative at certain values of applied potential bonds are formed between the metal and oxygen or hydrogen in aqueous and some non-aqueous solutions. Platinum also exhibits catalytic properties. 

---