论文部分内容阅读
本文从讨论金属结合能何以具有表面化学位移的原因开始，从金属团簇的一般性质出发，论证了金属结合能自尺寸大于1nm的团簇到金属微粒再到块体金属具有连续过渡性；金属结合能与粒径R呈正相关；与1／R具线性负相关关系，认为金微粒或团簇具有1．1eV以上的结合能负位移是可能的。并指出李九玲等同志在“评<含金硫化物矿物中不可能存在负价金>”一文中引用的某些衬底材料上的金团簇呈现结合能正位移的数据是由于这些金困簇已与其衬底材料发生了键合作用造成的，它们不能作为否定金属结合能位移与粒径呈正相关的依据。同时，笔者从“化学结合金”在氰化过程中并未被氧化成正离子金判断，它不应是负价金。并由同质并能位移与粒径可具负相关关系推论，“化学结合金”应是合企硫化物矿物中可存在的少量微粒碲金矿、碲金银矿等中的正离子金。笔者强调在讨论企的价态问题时应采用Allred－Rochow电负性数据而非常用的Pauling电负性数据，并再次指出含金硫化物矿物中不可能有负价金存在。
This paper starts from the reason why the metal bond can have surface chemical shift. Based on the general properties of the metal clusters, it is demonstrated that the metal binding energy has a continuous transition from the clusters larger than 1 nm to the metal particles and then to the bulk metal. The binding energies are positively correlated with particle size R, and negatively correlated with 1 / R. It is considered that it is possible that gold particles or clusters have a negative binding energy of 1.1eV or more. And pointed out that Li Jiling and other comrades in the “evaluation of gold sulfide minerals can not exist in the negative price of gold,” a paper cited in some of the substrate material on the gold cluster showing a positive binding energy shift data is due to the golden trap Has been bonded with its substrate material caused by the role, they can not serve as negative metal binding energy displacement and particle size was positively correlated basis. At the same time, the author from the “chemical bonding of gold” in the cyanide process has not been oxidized to positive ion gold judgment, it should not be negative price gold. And can be deduced from the fact that homogeneity and displacement can have a negative correlation with particle size. “Chemically bonded gold” should be positive ion gold in a small amount of fine grain tellurium gold and tellurium gold, silver and the like that may exist in the co-operative sulfide minerals. The author emphasizes that the Allred-Rochow electronegativity data rather than the commonly used Pauling electronegativity data should be used in the discussion of the valence state of the firm, and again points out that there is unlikely to be any negative gold in the gold-bearing sulphide minerals.