The Effects of Electronic Structure and Interatomic Bonding on the Soft X-Ray Al K Emission Spectrum from Aluminum Binary Systems

Abstract

AbstractThe aluminum K X-ray emission lines and bands from a series of aluminum binary alloys and other binary compounds were investigated using 6 kV electron excitation and a flat crystal vacuum spectrometer. The overall shape of the emission band and its energy position as a function of alloy composition was determined. It appears from the data that the aluminum K band undergoes changes in shape and energy position which are dependent on the electronic configuration of the element with which the aluminum is chemically bonded. These band changes can be interpreted as indicating a change in the bonding character between the metal atoms. In the Al-Ni system, for instance, the Al K band becomes more symmetrical and shifts to lower energy as the nickel content is increased, indicating that perhaps the bonding on the aluminum atoms is becoming less metallic and more covalent in nature as the nickel to aluminum ratio is increased.The aluminum Kα4/Kα3 satellite line intensity ratio also varies in an orderly manner in aluminum binary compounds. In general, these satellite line changes go hand-in-hand with the K band changes. If the K band shifts to lower energy, the Kα4/Kα3 intensity ratio will always increase in value.