Effect of low-temperature treatment on the state of gold hydrosol particles

A shift of the Plasmon absorption spectrum into the long-wave region, which increases with decreasing temperature and increasing duration of low-temperature treatment (LTT), was revealed after LTT at 217–77 K of Au hydrosol with a particle size of 10–11 nm. It was demonstrated that a decrease in the effective concentration of conduction electrons (N _e) after LTT is accompanied by an alteration in the damping coefficient of plasma resonance oscillations (γ) and the volume fraction of Au particles (N _V ). The temperature dependences of γ and N _V , just as for silver sol, are stipulated by the tunnel mechanism of the formation of low-temperature defects in the presence of two-dimensionally mobile positively charged aqua complexes X⁺(H₂O) _n . A feature of Au sol was revealed: the maximum on dependences of γ and N _V on the duration of LTT and the linear γ-N _e correlation.