Don't the interatomic distances depend on the lattice costant , which varies linearly with the composition of the 2?If it is as you say how can we draw a band diagram for an alloy?Useful nucleus said:Alloys can be ordered or random. IF the alloy is ordered , then their will be a set of well defined bond lengths (Si-Si, Ge-Ge, and Si-Ge). IF the alloy is random, then we will have a "spectrum" of bond lengths.
Yeah i thought the same a P type semiconductor can be considered an 'alloy' and the band diagram of is just the band diagram of the semiconductor with the only addition being the acceptor level. About higher concentration(50-50) if I understand correctly are you saying we can have '2' valence bands and by 2 I mean the valence band before the 'doping' and a valence band formed due to the injected atoms and they form a single energy band?Useful nucleus said:For a random alloy, the lattice parameter reported is an average over all unit cells. Each unit cell can have a slightly different lattice parameter than other unit cells. Thus, we have an average lattice constant but a distrubition of bond lengths.
The band diagram is a different story. If you have a dilue limit doping (say less than 1%), then the band diagram is the same for the host (99%) modified by dopant (or impurity) levels. Once the doping moves into the conecetrated alloy regime, the levels merge to form a continuous band of their own modifying the host original band diagram. Because of the formation of the new continuous bands, the collective band gap of the alloy can change dramatically (e.g. closing the gap and changing from a semiconductor to metal).
Interatomic spacing refers to the distance between adjacent atoms in a solid material. It is a key factor in determining the physical and chemical properties of materials, including their strength, conductivity, and reactivity.
The interatomic spacing in alloys can greatly impact their mechanical, electrical, and thermal properties. A smaller interatomic spacing can lead to stronger and more conductive alloys, while a larger spacing can result in weaker and less conductive alloys.
Interatomic spacing is typically measured using techniques such as X-ray diffraction or electron microscopy. These methods allow for the visualization and measurement of the distances between atoms in a material.
The interatomic spacing in alloys can be influenced by various factors, including the types of atoms present, their arrangement in the crystal structure, and the temperature and pressure conditions during the alloy's formation.
In most cases, interatomic spacing in alloys increases as temperature increases. This is due to the thermal expansion of the material, which causes the atoms to vibrate more and move further apart. However, there are some cases where interatomic spacing may decrease with temperature, such as in certain phase transitions or when alloying elements have different thermal expansion coefficients.