Critical Size Structure Parameters for Au Nanoparticles

Abstract

A model for calculating size dependent lattice volume of nanoparticles with that of the model for calculating size dependence melting point are applied to calculate nanoparticles structure parameters for Au in its critical size range smaller than 3 nm. From the method of trial and error for the melting temperature Tm, size dependence curve fitting to the experimental data is obtained. From this fitting curve, and both dependence of dmean versus Tm, and h versus dmean diagrams, the structure dependent parameters of bulk surface layer inter-planer distance h, vibrational entropy Svib, Tm and mean bond length dmean where found to have values of 0.2918 nm, 47 J. K-1.mol-1, 2500K and 0.2025 nm respectively. These parameters are the values for the expected bulk structure of the molecule like morphology for nanoparticles smaller than 3 nm diameter.

A Comprehensive Understanding of the Melting Temperature of Nanocrystals: Implications for Catalysis

“…For isolated NCs, with a decline in D , the proportion of surface atoms increases leading to the increase of A / V . According to Omar’s report, the surface bond length increases with the decrease of D , , which leads to the surface atoms have a higher energetic state than do the interior atoms. Then, the properties of the NCs of small size are primarily determined by the surface atoms.…”

Size dependent thermodynamic properties of nanoparticles

“…Figure 2. Melting temperature (Tn) at different size calculated for Au, compared with the experimental data [10],liquid drop model [27] and mean bonding length model Omer [28]. Figures 3-4 represent the results of size dependence of Debye temperature θDn for Si and Au nanoparticles calculated using Eq.…”