【摘要】 根据原子及离子中电子的行为与结合能之间的关系得到:结合能与颗粒粒径及离子价态均呈正相关。金微粒小至500nm左右时其结合能变至83eV。由此认为含金硫化物矿物XPS谱图上83eV附近的激发峰是由微包裹体金引起的。另据同质异能位移与离子s电子密度间的关系特征断定,“化学结合金”并非负价金;且由更准确的Allred-Rochow电负性数据判断,金不能类质同象取代硫。故可认为含金硫化物矿物中似不可能存在负价金。更多还原

【Abstract】 According to the directly proportional relationship between binding energy and attraction of excited inner electrons by the nucleus, it can be known that, when the positive ion valence gets higher, its attraction will be greater, and so does its binding energy. With regard to metal particles, because the outermost electrons of its surface atom are mostly bound up and seldom enter the lattice, the attraction of the surface atom is weaker than that of the inside one. As a result, the binding energy (V1) of the surface atom is weaker than that (V2) of the inside atom. Be-sides, as the metal particle becomes smaller, its ratio (M/N) of the surface atom’s number (M) tothe atom’s number (N) of the whole particle will become larger. The binding genergy (W) ofthe metal particle approximates to. It decreases as theratio (M/N) gets larger. So, there is also directly proportional relationship between W and the radius (R) of the metal particle.The relation of W and R is expressed as W = a .-1/R+b (both a and b are constants). Onthe basis of this formula and some relevant data, it is calculated that the W of the native gold particle with a radius of nearly 500 nm is close to 83 eV. So, the authors believe that the energy peak near 83 eV in the XPS chart of Au-bearing sulfide is not caused by negtive valence gold, but more possibly by microinclusion gold.Meanwhile, according to the relationship of the isomeric displacement and the density of the S electrons, the isomeric displacement will get greater with decrease in number of the outermost S electrons or increase in number of the subouter d electrons. Hence, the "chemical bound gold" must be positive ion gold, because its isomeric displacement is +3. 65±0. 05 mm/s, which is large relative to -1. 2±0. 1 mm/s of native gold. Further, it is pointed out that gold cannot replace sulfur isomorphously in sulfide, on the basis of more accurate data of Allred-Rochow elec-tronegativity. So, it is believed that there is no negative valence gold in Au-bearing sulfide.更多还原