Dear Researchers,
I have performed a DFT calculation on adsorption of formaldehyde molecule on single gold (Au) atom. I included relativistic effects in the calculation. The results show that formaldehyde adsorbed on the Au atom with much higher binding energy.
However, it is well known that gold is chemically inert and this contradicts with my DFT result.
Does chemical reactivity of single gold atom significantly differ from gold cluster/nano particles or bulk solid ??
Any help in this regard is highly appreciable...
Thanking you.
With regards,
Bibhas
Dear Bibhas,
of course, Au-atoms are not fully inert. Inert gases can form solids by attractive interactions, due to van der Waals interaction. The freezing temperature is a measure for the strength of interaction. The lowest cold point has He - only at high pressure. Look in the table - so higher the atomic weight, so heigher the freezing point. The melting point of gold is 1337 K and the boiling point 3243 K. That means, the atoms are "strongly" bound if they form a solid. The enthalpy of vaporization (342 kJ/mol) is a measure for the binding energy. You can yourself recalculate this energy in eV/atom but it is more than 1eV.
An individual atom can interact with other atoms like gold with gold. Whereas in a solid the bindings are (partially) saturated, a single atom is not. Therefore, a single atoms doesn't behave like a solid.
With Regards
R. Mitdank
Dear Bibhas Manna,
Please see the attached publications.
I hope those help.
Regards
Engin
The chemical activity of the gold atom is greater than the gold nanoparticles. Adsorption is the concentration of formaldehyde on the surface of gold nanoparticles as the Gibbs surface energy tends to a minimum. A chemical reaction is the desire of reactants (gold and formaldehyde atoms) to minimize the Gibbs energy of the reaction (possible oxidation of gold, the breakdown of formaldehyde molecules). Relativistic effects are negligible with these transformations.
- Badges
- Science topic
- Similar topics
- Chemistry
- Nanotechnology
- Nano